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<img id="head-icon" alt="Nimrod logo"
src="logo2.png" />
</div>
<div class="slide">
<h1 class="title">The ultimate introduction</h1>
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<center><big><big>Slides</big></big></center>
<br />
<center><big><big><big><big>git clone https://github.com/Araq/oscon2015</big></big></big></big></center>
<br />
<br />
<br />
<center><big><big>Download</big></big></center>
<br />
<center><big><big><big><big><a href="http://nim-lang.org/download.html">http://nim-lang.org/download.html</a></big></big></big></big></center>
</div>
<div class="slide">
<h1 id="installation">Installation</h1><pre>git clone -b devel git://github.com/nim-lang/Nim.git
cd Nim
git clone -b devel --depth 1 git://github.com/nim-lang/csources
cd csources && sh build.sh
cd ..
bin/nim c koch
./koch boot -d:release</pre>
</div>
<div class="slide">
<h1 id="what-is-nim">What is Nim?</h1><ul class="simple"><li>new <strong>systems</strong> programming language</li>
<li>compiles to C</li>
<li>garbage collection + manual memory management</li>
<li>thread local garbage collection</li>
<li>design goals: efficient, expressive, elegant</li>
</ul>
</div>
<div class="slide">
<h1 id="philosophy">Philosophy</h1><ul class="simple"><li>power</li>
<li>efficiency</li>
<li>fun</li>
</ul>
</div>
<div class="slide">
<h1 id="why-nim">Why Nim?</h1><ul class="simple"><li>Major influences: Modula 3, Delphi, Ada, C++, Python, Lisp, Oberon.</li>
<li>Development started in 2006</li>
<li>First successful bootstrapping in 2008<ul class="simple"><li>compiler written in Delphi</li>
<li>converted to Nim via "pas2nim"</li>
</ul>
</li>
</ul>
</div>
<div class="slide">
<h1 id="uses-of-nim">Uses of Nim</h1><ul class="simple"><li>games</li>
<li>compilers</li>
<li>operating system development</li>
<li>scientific computing</li>
<li>scripting</li>
</ul>
</div>
<div class="slide">
<h1 id="nim-at-3dicc">Nim at 3dicc</h1><img src="busyteam2.png" />
</div>
<div class="slide">
<h1 id="urls">URLs</h1><table border="1" class="docutils"><tr><td>Website</td><td><a class="reference external" href="http://nim-lang.org">http://nim-lang.org</a></td></tr>
<tr><td>Mailing list</td><td><a class="reference external" href="http://www.freelists.org/list/nim-dev">http://www.freelists.org/list/nim-dev</a></td></tr>
<tr><td>Forum</td><td><a class="reference external" href="http://forum.nim-lang.org">http://forum.nim-lang.org</a></td></tr>
<tr><td>Github</td><td><a class="reference external" href="https://github.com/Araq/Nim">https://github.com/Araq/Nim</a></td></tr>
<tr><td>IRC</td><td>irc.freenode.net/nim</td></tr>
</table>
</div>
<div class="slide">
<h1 id="hello-world">Hello World</h1><pre id="listing_1" class="listing"><span class="Identifier">echo</span> <span class="StringLit">"hello world!"</span></pre>
</div>
<div class="slide">
<h1 id="hello-world">Hello World</h1><pre id="listing_2" class="listing"><span class="Identifier">echo</span> <span class="StringLit">"hello world!"</span></pre><pre>nim c -r hello.nim</pre>
</div>
<div class="slide">
<h1 id="more-code">More Code!</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
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7
8
9
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12
13
14
15
</pre></td><td><pre id="listing_3" class="listing"><span class="Keyword">proc</span> <span class="Identifier">decimalToRoman</span><span class="Operator">*</span><span class="Punctuation">(</span><span class="Identifier">number</span><span class="Punctuation">:</span> <span class="Identifier">range</span><span class="Punctuation">[</span><span class="FloatNumber">1.</span><span class="Operator">.</span><span class="DecNumber">3_999</span><span class="Punctuation">]</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">string</span> <span class="Operator">=</span>
<span class="Comment">## Converts a number to a Roman numeral.</span>
<span class="Keyword">const</span> <span class="Identifier">romanComposites</span> <span class="Operator">=</span> <span class="Punctuation">{</span>
<span class="StringLit">"M"</span><span class="Punctuation">:</span> <span class="DecNumber">1000</span><span class="Punctuation">,</span> <span class="StringLit">"CM"</span><span class="Punctuation">:</span> <span class="DecNumber">900</span><span class="Punctuation">,</span>
<span class="StringLit">"D"</span><span class="Punctuation">:</span> <span class="DecNumber">500</span><span class="Punctuation">,</span> <span class="StringLit">"CD"</span><span class="Punctuation">:</span> <span class="DecNumber">400</span><span class="Punctuation">,</span> <span class="StringLit">"C"</span><span class="Punctuation">:</span> <span class="DecNumber">100</span><span class="Punctuation">,</span>
<span class="StringLit">"XC"</span><span class="Punctuation">:</span> <span class="DecNumber">90</span><span class="Punctuation">,</span> <span class="StringLit">"L"</span><span class="Punctuation">:</span> <span class="DecNumber">50</span><span class="Punctuation">,</span> <span class="StringLit">"XL"</span><span class="Punctuation">:</span> <span class="DecNumber">40</span><span class="Punctuation">,</span> <span class="StringLit">"X"</span><span class="Punctuation">:</span> <span class="DecNumber">10</span><span class="Punctuation">,</span> <span class="StringLit">"IX"</span><span class="Punctuation">:</span> <span class="DecNumber">9</span><span class="Punctuation">,</span>
<span class="StringLit">"V"</span><span class="Punctuation">:</span> <span class="DecNumber">5</span><span class="Punctuation">,</span> <span class="StringLit">"IV"</span><span class="Punctuation">:</span> <span class="DecNumber">4</span><span class="Punctuation">,</span> <span class="StringLit">"I"</span><span class="Punctuation">:</span> <span class="DecNumber">1</span><span class="Punctuation">}</span>
<span class="Identifier">result</span> <span class="Operator">=</span> <span class="StringLit">""</span>
<span class="Keyword">var</span> <span class="Identifier">decVal</span> <span class="Operator">=</span> <span class="Identifier">number</span><span class="Operator">.</span><span class="Identifier">int</span>
<span class="Keyword">for</span> <span class="Identifier">key</span><span class="Punctuation">,</span> <span class="Identifier">val</span> <span class="Keyword">in</span> <span class="Identifier">items</span><span class="Punctuation">(</span><span class="Identifier">romanComposites</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Keyword">while</span> <span class="Identifier">decVal</span> <span class="Operator">>=</span> <span class="Identifier">val</span><span class="Punctuation">:</span>
<span class="Identifier">decVal</span> <span class="Operator">-=</span> <span class="Identifier">val</span>
<span class="Identifier">result</span><span class="Operator">.</span><span class="Identifier">add</span><span class="Punctuation">(</span><span class="Identifier">key</span><span class="Punctuation">)</span>
<span class="Identifier">echo</span> <span class="Identifier">decimalToRoman</span><span class="Punctuation">(</span><span class="DecNumber">1009</span><span class="Punctuation">)</span> <span class="Comment"># MIX</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_3')">Select</button><ul class="simple"><li><tt class="docutils literal"><span class="pre">{"M": 1000, "CM": 900}</span></tt> sugar for <tt class="docutils literal"><span class="pre">[("M", 1000), ("CM", 900)]</span></tt></li>
<li><tt class="docutils literal"><span class="pre">result</span></tt> implicitly available</li>
</ul>
</div>
<div class="slide">
<h1 id="nimble">Nimble</h1><ul class="simple"><li>Live demo.</li>
</ul>
</div>
<div class="slide">
<h1 id="function-application">Function application</h1><p>Function application is <tt class="docutils literal"><span class="pre">f()</span></tt>, <tt class="docutils literal"><span class="pre">f(a)</span></tt>, <tt class="docutils literal"><span class="pre">f(a, b)</span></tt>.</p>
</div>
<div class="slide">
<h1 id="function-application">Function application</h1><p>Function application is <tt class="docutils literal"><span class="pre">f()</span></tt>, <tt class="docutils literal"><span class="pre">f(a)</span></tt>, <tt class="docutils literal"><span class="pre">f(a, b)</span></tt>.</p>
<p>And here is the sugar:</p>
<table border="1" class="docutils"><tr><th>Sugar</th><th>Meaning</th><th>Example</th></tr>
<tr><td><tt class="docutils literal"><span class="pre">f a</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a)</span></tt></td><td><tt class="docutils literal"><span class="pre">spawn log("some message")</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f()</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a)</span></tt></td><td><tt class="docutils literal"><span class="pre">db.fetchRow()</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a)</span></tt></td><td><tt class="docutils literal"><span class="pre">mystring.len</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">f a, b</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a, b)</span></tt></td><td><tt class="docutils literal"><span class="pre">echo "hello ", "world"</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f(b)</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a, b)</span></tt></td><td><tt class="docutils literal"><span class="pre">myarray.map(f)</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f b</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a, b)</span></tt></td><td><tt class="docutils literal"><span class="pre">db.fetchRow 1</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">f"\n"</span></tt></td><td><tt class="docutils literal"><span class="pre">f(r"\n")</span></tt></td><td><tt class="docutils literal"><span class="pre">re"\b[a-z*]\b"</span></tt></td></tr>
</table>
</div>
<div class="slide">
<h1 id="function-application">Function application</h1><p>Function application is <tt class="docutils literal"><span class="pre">f()</span></tt>, <tt class="docutils literal"><span class="pre">f(a)</span></tt>, <tt class="docutils literal"><span class="pre">f(a, b)</span></tt>.</p>
<p>And here is the sugar:</p>
<table border="1" class="docutils"><tr><th>Sugar</th><th>Meaning</th><th>Example</th></tr>
<tr><td><tt class="docutils literal"><span class="pre">f a</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a)</span></tt></td><td><tt class="docutils literal"><span class="pre">spawn log("some message")</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f()</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a)</span></tt></td><td><tt class="docutils literal"><span class="pre">db.fetchRow()</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a)</span></tt></td><td><tt class="docutils literal"><span class="pre">mystring.len</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">f a, b</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a, b)</span></tt></td><td><tt class="docutils literal"><span class="pre">echo "hello ", "world"</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f(b)</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a, b)</span></tt></td><td><tt class="docutils literal"><span class="pre">myarray.map(f)</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">a.f b</span></tt></td><td><tt class="docutils literal"><span class="pre">f(a, b)</span></tt></td><td><tt class="docutils literal"><span class="pre">db.fetchRow 1</span></tt></td></tr>
<tr><td><tt class="docutils literal"><span class="pre">f"\n"</span></tt></td><td><tt class="docutils literal"><span class="pre">f(r"\n")</span></tt></td><td><tt class="docutils literal"><span class="pre">re"\b[a-z*]\b"</span></tt></td></tr>
</table><p><strong>BUT</strong>: <tt class="docutils literal"><span class="pre">f</span></tt> does not mean <tt class="docutils literal"><span class="pre">f()</span></tt>; <tt class="docutils literal"><span class="pre">myarray.map(f)</span></tt> passes <tt class="docutils literal"><span class="pre">f</span></tt> to <tt class="docutils literal"><span class="pre">map</span></tt></p>
</div>
<div class="slide">
<h1 id="operators">Operators</h1><ul class="simple"><li>operators are simply sugar for functions</li>
<li>operator in backticks is treated like an identifier<pre>`@`(x, y)
x.`@`(y)
`@`(x)
x.`@`()
x.`@`</pre>
</li>
</ul>
</div>
<div class="slide">
<h1 id="operators">Operators</h1><ul class="simple"><li>Of course, most of the time binary operators are simply invoked as <tt class="docutils literal"><span class="pre">x @ y</span></tt> and unary operators as <tt class="docutils literal"><span class="pre">@x</span></tt>.</li>
<li>No explicit distinction between binary and unary operators:</li>
</ul>
<table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
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</pre></td><td><pre id="listing_4" class="listing"><span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Operator">++</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">int</span><span class="Punctuation">;</span> <span class="Identifier">y</span><span class="Punctuation">:</span> <span class="Identifier">int</span> <span class="Operator">=</span> <span class="DecNumber">1</span><span class="Punctuation">;</span> <span class="Identifier">z</span><span class="Punctuation">:</span> <span class="Identifier">int</span> <span class="Operator">=</span> <span class="DecNumber">0</span><span class="Punctuation">)</span> <span class="Operator">=</span>
<span class="Identifier">x</span> <span class="Operator">=</span> <span class="Identifier">x</span> <span class="Operator">+</span> <span class="Identifier">y</span> <span class="Operator">+</span> <span class="Identifier">z</span>
<span class="Keyword">var</span> <span class="Identifier">g</span> <span class="Operator">=</span> <span class="DecNumber">70</span>
<span class="Operator">++</span><span class="Identifier">g</span>
<span class="Identifier">g</span> <span class="Operator">++</span> <span class="DecNumber">7</span>
<span class="Identifier">g</span><span class="Operator">.</span><span class="Punctuation">`</span><span class="Operator">++</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="DecNumber">10</span><span class="Punctuation">,</span> <span class="DecNumber">20</span><span class="Punctuation">)</span>
<span class="Identifier">echo</span> <span class="Identifier">g</span> <span class="Comment"># writes 108</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_4')">Select</button><ul class="simple"><li>parameters are readonly unless declared as <tt class="docutils literal"><span class="pre">var</span></tt></li>
<li><tt class="docutils literal"><span class="pre">var</span></tt> means "pass by reference" (implemented with a hidden pointer)</li>
</ul>
</div>
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<h1 id="control-flow">Control flow</h1><ul class="simple"><li>The usual control flow statements are available:<ul class="simple"><li>if</li>
<li>case</li>
<li>when</li>
<li>while</li>
<li>for</li>
<li>try</li>
<li>defer</li>
<li>return</li>
<li>yield</li>
</ul>
</li>
</ul>
</div>
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<h1 id="if-vs-when">If vs when</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
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</pre></td><td><pre id="listing_5" class="listing"><span class="Keyword">when</span> <span class="Identifier">defined</span><span class="Punctuation">(</span><span class="Identifier">posix</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Keyword">proc</span> <span class="Identifier">getCreationTime</span><span class="Punctuation">(</span><span class="Identifier">file</span><span class="Punctuation">:</span> <span class="Identifier">string</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">Time</span> <span class="Operator">=</span>
<span class="Keyword">var</span> <span class="Identifier">res</span><span class="Punctuation">:</span> <span class="Identifier">Stat</span>
<span class="Keyword">if</span> <span class="Identifier">stat</span><span class="Punctuation">(</span><span class="Identifier">file</span><span class="Punctuation">,</span> <span class="Identifier">res</span><span class="Punctuation">)</span> <span class="Operator"><</span> <span class="DecNumber">0'i32</span><span class="Punctuation">:</span>
<span class="Keyword">let</span> <span class="Identifier">error</span> <span class="Operator">=</span> <span class="Identifier">osLastError</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Identifier">raiseOSError</span><span class="Punctuation">(</span><span class="Identifier">error</span><span class="Punctuation">)</span>
<span class="Keyword">return</span> <span class="Identifier">res</span><span class="Operator">.</span><span class="Identifier">st_ctime</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_5')">Select</button>
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<h1 id="statements-vs-expressions">Statements vs expressions</h1><p>Statements require indentation:</p>
<pre id="listing_6" class="listing"><span class="Comment"># no indentation needed for single assignment statement:</span>
<span class="Keyword">if</span> <span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">x</span> <span class="Operator">=</span> <span class="Identifier">false</span>
<span class="Comment"># indentation needed for nested if statement:</span>
<span class="Keyword">if</span> <span class="Identifier">x</span><span class="Punctuation">:</span>
<span class="Keyword">if</span> <span class="Identifier">y</span><span class="Punctuation">:</span>
<span class="Identifier">y</span> <span class="Operator">=</span> <span class="Identifier">false</span>
<span class="Keyword">else</span><span class="Punctuation">:</span>
<span class="Identifier">y</span> <span class="Operator">=</span> <span class="Identifier">true</span>
<span class="Comment"># indentation needed, because two statements follow the condition:</span>
<span class="Keyword">if</span> <span class="Identifier">x</span><span class="Punctuation">:</span>
<span class="Identifier">x</span> <span class="Operator">=</span> <span class="Identifier">false</span>
<span class="Identifier">y</span> <span class="Operator">=</span> <span class="Identifier">false</span></pre>
</div>
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<h1 id="statements-vs-expressions">Statements vs expressions</h1><p>Expressions do not:</p>
<pre id="listing_7" class="listing"><span class="Keyword">if</span> <span class="Identifier">thisIsaLongCondition</span><span class="Punctuation">(</span><span class="Punctuation">)</span> <span class="Keyword">and</span>
<span class="Identifier">thisIsAnotherLongCondition</span><span class="Punctuation">(</span><span class="DecNumber">1</span><span class="Punctuation">,</span>
<span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">,</span> <span class="DecNumber">4</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Identifier">x</span> <span class="Operator">=</span> <span class="Identifier">true</span></pre><ul class="simple"><li>Rule of thumb: optional indentation after operators, <tt class="docutils literal"><span class="pre">(</span></tt> and <tt class="docutils literal"><span class="pre">,</span></tt></li>
<li><tt class="docutils literal"><span class="pre">if</span></tt>, <tt class="docutils literal"><span class="pre">case</span></tt> etc also available as expressions</li>
</ul>
</div>
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<h1 id="builtin-types">Builtin types</h1><ul class="simple"><li><tt class="docutils literal"><span class="pre">int</span></tt> -- platform dependent (16) 32 or 64 bit signed number<ul class="simple"><li>overflows produce an exception in debug mode; wrap around in release mode</li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">float</span></tt> -- 64 bit floating point number<ul class="simple"><li>float64 an alias for float</li>
<li>float32 32 bit floating point number</li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">int8</span></tt> / <tt class="docutils literal"><span class="pre">int16</span></tt> / <tt class="docutils literal"><span class="pre">int32</span></tt> / <tt class="docutils literal"><span class="pre">int64</span></tt><ul class="simple"><li>integer types with a platform independent size</li>
</ul>
</li>
</ul>
</div>
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<h1 id="builtin-types">Builtin types</h1><ul class="simple"><li><tt class="docutils literal"><span class="pre">uint</span></tt> / <tt class="docutils literal"><span class="pre">uint8</span></tt> / <tt class="docutils literal"><span class="pre">uint16</span></tt> / <tt class="docutils literal"><span class="pre">uint32</span></tt> / <tt class="docutils literal"><span class="pre">uint64</span></tt><ul class="simple"><li>like in C, always wrap around; modulo arithmetic</li>
<li>heavily discouraged: <tt class="docutils literal"><span class="pre">for in 0 .. x.len - 3</span></tt> should iterate 0 times when <tt class="docutils literal"><span class="pre">x.len == 0</span></tt>, not 4294967293 times!</li>
<li>instead: use <tt class="docutils literal"><span class="pre">Natural</span></tt></li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">range[T]</span></tt><ul class="simple"><li>subrange type; quite heavily used in Nim (<tt class="docutils literal"><span class="pre">type Natural = range[0..high(int)]</span></tt>)</li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">bool</span></tt></li>
</ul>
</div>
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<h1 id="builtin-types">Builtin types</h1><ul class="simple"><li><tt class="docutils literal"><span class="pre">array[FixedSize, T]</span></tt><ul class="simple"><li>fixed size in Nim</li>
<li>value based datatypes</li>
<li>layout is compatible to C</li>
<li>create via <tt class="docutils literal"><span class="pre">[1, 2, 3]</span></tt> construction</li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">seq[T]</span></tt><ul class="simple"><li>dynamically resizable at runtime</li>
<li>grow with <tt class="docutils literal"><span class="pre">add</span></tt>, resize with <tt class="docutils literal"><span class="pre">setLen</span></tt></li>
<li>create via <tt class="docutils literal"><span class="pre">@</span></tt> or <tt class="docutils literal"><span class="pre">newSeq</span></tt>: <tt class="docutils literal"><span class="pre">@[1, 2, 3]</span></tt></li>
<li>allocated on the heap and GC'ed</li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">openArray[T]</span></tt><ul class="simple"><li>allows to pass <tt class="docutils literal"><span class="pre">seq</span></tt> or <tt class="docutils literal"><span class="pre">array</span></tt> to a routine</li>
<li>internally a (pointer, length) pair</li>
</ul>
</li>
</ul>
</div>
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<h1 id="builtin-types">Builtin types</h1><ul class="simple"><li><tt class="docutils literal"><span class="pre">proc (a, b: string) {.closure.}</span></tt><ul class="simple"><li>functions are first class in Nim</li>
<li>"calling convention" affects type compatibility</li>
<li><tt class="docutils literal"><span class="pre">closure</span></tt> is a special calling convention (closures are GC'ed)</li>
</ul>
</li>
<li><tt class="docutils literal"><span class="pre">char</span></tt> / <tt class="docutils literal"><span class="pre">string</span></tt> / <tt class="docutils literal"><span class="pre">cstring</span></tt><ul class="simple"><li><tt class="docutils literal"><span class="pre">char</span></tt> is simply an octet, <tt class="docutils literal"><span class="pre">string</span></tt> is almost a <tt class="docutils literal"><span class="pre">seq[char]</span></tt>.</li>
<li><tt class="docutils literal"><span class="pre">string</span></tt> is (usually) allocated on the heap and GC'ed</li>
</ul>
</li>
</ul>
</div>
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<h1 id="builtin-types">Builtin types</h1><p><tt class="docutils literal"><span class="pre">tuple</span></tt></p>
<ul class="simple"><li>value based datatypes</li>
<li>structural typing</li>
<li>optional field names</li>
<li>construct with <tt class="docutils literal"><span class="pre">()</span></tt></li>
</ul>
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</pre></td><td><pre id="listing_8" class="listing"><span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Operator">+-</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">,</span> <span class="Identifier">y</span><span class="Punctuation">:</span> <span class="Identifier">int</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Punctuation">(</span><span class="Identifier">int</span><span class="Punctuation">,</span> <span class="Identifier">int</span><span class="Punctuation">)</span> <span class="Operator">=</span> <span class="Punctuation">(</span><span class="Identifier">x</span> <span class="Operator">-</span> <span class="Identifier">y</span><span class="Punctuation">,</span> <span class="Identifier">x</span> <span class="Operator">+</span> <span class="Identifier">y</span><span class="Punctuation">)</span>
<span class="Comment"># alternatively</span>
<span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Operator">+-</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">,</span> <span class="Identifier">y</span><span class="Punctuation">:</span> <span class="Identifier">int</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Keyword">tuple</span><span class="Punctuation">[</span><span class="Identifier">lowerBound</span><span class="Punctuation">,</span> <span class="Identifier">upperBound</span><span class="Punctuation">:</span> <span class="Identifier">int</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="Punctuation">(</span><span class="Identifier">x</span> <span class="Operator">-</span> <span class="Identifier">y</span><span class="Punctuation">,</span> <span class="Identifier">x</span> <span class="Operator">+</span> <span class="Identifier">y</span><span class="Punctuation">)</span>
<span class="Keyword">let</span> <span class="Identifier">tup</span> <span class="Operator">=</span> <span class="DecNumber">100</span> <span class="Operator">+-</span> <span class="DecNumber">10</span>
<span class="Identifier">echo</span> <span class="Identifier">tup</span><span class="Punctuation">[</span><span class="DecNumber">0</span><span class="Punctuation">]</span><span class="Punctuation">,</span> <span class="StringLit">" "</span><span class="Punctuation">,</span> <span class="Identifier">tup</span><span class="Operator">.</span><span class="Identifier">upperBound</span>
<span class="Comment"># tuple unpacking</span>
<span class="Keyword">let</span> <span class="Punctuation">(</span><span class="Identifier">lower</span><span class="Punctuation">,</span> <span class="Identifier">_</span><span class="Punctuation">)</span> <span class="Operator">=</span> <span class="DecNumber">100</span> <span class="Operator">+-</span> <span class="DecNumber">10</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_8')">Select</button>
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<h1 id="builtin-types">Builtin types</h1><p><tt class="docutils literal"><span class="pre">object</span></tt></p>
<ul class="simple"><li>value based datatypes</li>
</ul>
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</pre></td><td><pre id="listing_9" class="listing"><span class="Keyword">type</span>
<span class="Identifier">Rect</span> <span class="Operator">=</span> <span class="Keyword">object</span>
<span class="Identifier">x</span><span class="Punctuation">,</span> <span class="Identifier">y</span><span class="Punctuation">,</span> <span class="Identifier">w</span><span class="Punctuation">,</span> <span class="Identifier">h</span><span class="Punctuation">:</span> <span class="Identifier">int</span>
<span class="Comment"># construction:</span>
<span class="Keyword">let</span> <span class="Identifier">r</span> <span class="Operator">=</span> <span class="Identifier">Rect</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="DecNumber">12</span><span class="Punctuation">,</span> <span class="Identifier">y</span><span class="Punctuation">:</span> <span class="DecNumber">22</span><span class="Punctuation">,</span> <span class="Identifier">w</span><span class="Punctuation">:</span> <span class="DecNumber">40</span><span class="Punctuation">,</span> <span class="Identifier">h</span><span class="Punctuation">:</span> <span class="DecNumber">80</span><span class="Punctuation">)</span>
<span class="Comment"># field access:</span>
<span class="Identifier">echo</span> <span class="Identifier">r</span><span class="Operator">.</span><span class="Identifier">x</span><span class="Punctuation">,</span> <span class="StringLit">" "</span><span class="Punctuation">,</span> <span class="Identifier">r</span><span class="Operator">.</span><span class="Identifier">y</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_9')">Select</button>
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<h1 id="builtin-types">Builtin types</h1><p>enums & sets</p>
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</pre></td><td><pre id="listing_10" class="listing"><span class="Keyword">type</span>
<span class="Identifier">SandboxFlag</span><span class="Operator">*</span> <span class="Operator">=</span> <span class="Keyword">enum</span> <span class="Comment">## what the interpreter should allow</span>
<span class="Identifier">allowCast</span><span class="Punctuation">,</span> <span class="Comment">## allow unsafe language feature: 'cast'</span>
<span class="Identifier">allowFFI</span><span class="Punctuation">,</span> <span class="Comment">## allow the FFI</span>
<span class="Identifier">allowInfiniteLoops</span> <span class="Comment">## allow endless loops</span>
<span class="Identifier">SandboxFlags</span><span class="Operator">*</span> <span class="Operator">=</span> <span class="Identifier">set</span><span class="Punctuation">[</span><span class="Identifier">SandboxFlag</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Identifier">runNimCode</span><span class="Punctuation">(</span><span class="Identifier">code</span><span class="Punctuation">:</span> <span class="Identifier">string</span><span class="Punctuation">;</span> <span class="Identifier">flags</span><span class="Punctuation">:</span> <span class="Identifier">SandboxFlags</span> <span class="Operator">=</span> <span class="Punctuation">{</span><span class="Identifier">allowCast</span><span class="Punctuation">,</span> <span class="Identifier">allowFFI</span><span class="Punctuation">}</span><span class="Punctuation">)</span> <span class="Operator">=</span>
<span class="Operator">...</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_10')">Select</button>
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<h1 id="builtin-types">Builtin types</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
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</pre></td><td><pre id="listing_11" class="listing"><span class="Preprocessor">#define</span> <span class="Identifier">allowCast</span> <span class="Punctuation">(</span><span class="DecNumber">1</span> <span class="Operator"><<</span> <span class="DecNumber">0</span><span class="Punctuation">)</span>
<span class="Preprocessor">#define</span> <span class="Identifier">allowFFI</span> <span class="Punctuation">(</span><span class="DecNumber">1</span> <span class="Operator"><<</span> <span class="DecNumber">1</span><span class="Punctuation">)</span>
<span class="Preprocessor">#define</span> <span class="Identifier">allowInfiniteLoops</span> <span class="Punctuation">(</span><span class="DecNumber">1</span> <span class="Operator"><<</span> <span class="DecNumber">1</span><span class="Punctuation">)</span>
<span class="Keyword">void</span> <span class="Identifier">runNimCode</span><span class="Punctuation">(</span><span class="Keyword">char</span><span class="Operator">*</span> <span class="Identifier">code</span><span class="Punctuation">,</span> <span class="Keyword">unsigned</span> <span class="Keyword">int</span> <span class="Identifier">flags</span> <span class="Operator">=</span> <span class="Identifier">allowCast</span><span class="Operator">|</span><span class="Identifier">allowFFI</span><span class="Punctuation">)</span><span class="Punctuation">;</span>
<span class="Identifier">runNimCode</span><span class="Punctuation">(</span><span class="StringLit">"4+5"</span><span class="Punctuation">,</span> <span class="DecNumber">700</span><span class="Punctuation">)</span><span class="Punctuation">;</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_11')">Select</button>
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<div class="slide">
<h1 id="builtin-types">Builtin types</h1><p><tt class="docutils literal"><span class="pre">ref</span></tt> and <tt class="docutils literal"><span class="pre">ptr</span></tt></p>
<ul class="simple"><li>pointers; <tt class="docutils literal"><span class="pre">ref</span></tt> is a "traced" pointer, <tt class="docutils literal"><span class="pre">ptr</span></tt> is an "untraced" pointer</li>
<li><tt class="docutils literal"><span class="pre">string</span></tt>, <tt class="docutils literal"><span class="pre">seq</span></tt>, <tt class="docutils literal"><span class="pre">ref</span></tt> and <tt class="docutils literal"><span class="pre">closure</span></tt> are GC'ed, nothing else</li>
<li><tt class="docutils literal"><span class="pre">ref object</span></tt> an idiom to get reference semantics out of objects</li>
</ul>
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<h1 id="regular-expressions">Regular expressions</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
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</pre></td><td><pre id="listing_12" class="listing"><span class="Comment"># Model a regular expression</span>
<span class="Keyword">type</span>
<span class="Identifier">RegexKind</span> <span class="Operator">=</span> <span class="Keyword">enum</span> <span class="Comment">## the regex AST's kind</span>
<span class="Identifier">reChar</span><span class="Punctuation">,</span> <span class="Comment">## character node "c"</span>
<span class="Identifier">reCClass</span><span class="Punctuation">,</span> <span class="Comment">## character class node "[a-z]"</span>
<span class="Identifier">reStar</span><span class="Punctuation">,</span> <span class="Comment">## star node "r*"</span>
<span class="Identifier">rePlus</span><span class="Punctuation">,</span> <span class="Comment">## plus node "r+"</span>
<span class="Identifier">reOpt</span><span class="Punctuation">,</span> <span class="Comment">## option node "r?"</span>
<span class="Identifier">reCat</span><span class="Punctuation">,</span> <span class="Comment">## concatenation node "ab"</span>
<span class="Identifier">reAlt</span><span class="Punctuation">,</span> <span class="Comment">## alternatives node "a|b"</span>
<span class="Identifier">reWordBoundary</span> <span class="Comment">## "\b"</span>
<span class="Identifier">RegExpr</span> <span class="Operator">=</span> <span class="Keyword">ref</span> <span class="Keyword">object</span>
<span class="Keyword">case</span> <span class="Identifier">kind</span><span class="Punctuation">:</span> <span class="Identifier">RegexKind</span>
<span class="Keyword">of</span> <span class="Identifier">reWordBoundary</span><span class="Punctuation">:</span> <span class="Keyword">discard</span>
<span class="Keyword">of</span> <span class="Identifier">reChar</span><span class="Punctuation">:</span>
<span class="Identifier">c</span><span class="Punctuation">:</span> <span class="Identifier">char</span>
<span class="Keyword">of</span> <span class="Identifier">reCClass</span><span class="Punctuation">:</span>
<span class="Identifier">cc</span><span class="Punctuation">:</span> <span class="Identifier">set</span><span class="Punctuation">[</span><span class="Identifier">char</span><span class="Punctuation">]</span>
<span class="Keyword">of</span> <span class="Identifier">reStar</span><span class="Punctuation">,</span> <span class="Identifier">rePlus</span><span class="Punctuation">,</span> <span class="Identifier">reOpt</span><span class="Punctuation">:</span>
<span class="Identifier">child0</span><span class="Punctuation">:</span> <span class="Identifier">RegExpr</span>
<span class="Keyword">of</span> <span class="Identifier">reCat</span><span class="Punctuation">,</span> <span class="Identifier">reAlt</span><span class="Punctuation">:</span>
<span class="Identifier">child1</span><span class="Punctuation">,</span> <span class="Identifier">child2</span><span class="Punctuation">:</span> <span class="Identifier">RegExpr</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_12')">Select</button>
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<h1 id="equality">Equality</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
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9
</pre></td><td><pre id="listing_13" class="listing"><span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Operator">==</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Punctuation">,</span> <span class="Identifier">b</span><span class="Punctuation">:</span> <span class="Identifier">RegExpr</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">bool</span> <span class="Operator">=</span>
<span class="Keyword">if</span> <span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">kind</span> <span class="Operator">==</span> <span class="Identifier">b</span><span class="Operator">.</span><span class="Identifier">kind</span><span class="Punctuation">:</span>
<span class="Keyword">case</span> <span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">kind</span>
<span class="Keyword">of</span> <span class="Identifier">reWordBoundary</span><span class="Punctuation">:</span> <span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">true</span>
<span class="Keyword">of</span> <span class="Identifier">reChar</span><span class="Punctuation">:</span> <span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">c</span> <span class="Operator">==</span> <span class="Identifier">b</span><span class="Operator">.</span><span class="Identifier">c</span>
<span class="Keyword">of</span> <span class="Identifier">reCClass</span><span class="Punctuation">:</span> <span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">cc</span> <span class="Operator">==</span> <span class="Identifier">b</span><span class="Operator">.</span><span class="Identifier">cc</span>
<span class="Keyword">of</span> <span class="Identifier">reStar</span><span class="Punctuation">,</span> <span class="Identifier">rePlus</span><span class="Punctuation">,</span> <span class="Identifier">reOpt</span><span class="Punctuation">:</span> <span class="Identifier">result</span> <span class="Operator">=</span> <span class="Punctuation">`</span><span class="Operator">==</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">child0</span><span class="Punctuation">,</span> <span class="Identifier">b</span><span class="Operator">.</span><span class="Identifier">child0</span><span class="Punctuation">)</span>
<span class="Keyword">of</span> <span class="Identifier">reCat</span><span class="Punctuation">,</span> <span class="Identifier">reAlt</span><span class="Punctuation">:</span> <span class="Identifier">result</span> <span class="Operator">=</span> <span class="Punctuation">`</span><span class="Operator">==</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">child1</span><span class="Punctuation">,</span> <span class="Identifier">b</span><span class="Operator">.</span><span class="Identifier">child1</span><span class="Punctuation">)</span> <span class="Keyword">and</span>
<span class="Punctuation">`</span><span class="Operator">==</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Operator">.</span><span class="Identifier">child2</span><span class="Punctuation">,</span> <span class="Identifier">b</span><span class="Operator">.</span><span class="Identifier">child2</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_13')">Select</button>
</div>
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<h1 id="accessors">Accessors</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
</pre></td><td><pre id="listing_14" class="listing"><span class="Keyword">type</span>
<span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="Keyword">object</span>
<span class="Identifier">data</span><span class="Punctuation">:</span> <span class="Identifier">seq</span><span class="Punctuation">[</span><span class="Punctuation">(</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">)</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Identifier">hash</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">K</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">int</span> <span class="Operator">=</span> <span class="DecNumber">0</span>
<span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Punctuation">[</span><span class="Punctuation">]</span><span class="Punctuation">`</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">;</span> <span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">K</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">V</span> <span class="Operator">=</span>
<span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">x</span><span class="Operator">.</span><span class="Identifier">data</span><span class="Punctuation">[</span><span class="Identifier">hash</span><span class="Punctuation">(</span><span class="Identifier">k</span><span class="Punctuation">)</span><span class="Punctuation">]</span><span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Punctuation">[</span><span class="Punctuation">]</span><span class="Operator">=</span><span class="Punctuation">`</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">;</span> <span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">v</span><span class="Punctuation">:</span> <span class="Identifier">V</span><span class="Punctuation">)</span> <span class="Operator">=</span>
<span class="Identifier">x</span><span class="Operator">.</span><span class="Identifier">data</span><span class="Punctuation">[</span><span class="Identifier">hash</span><span class="Punctuation">(</span><span class="Identifier">k</span><span class="Punctuation">)</span><span class="Punctuation">]</span><span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="Identifier">v</span>
<span class="Keyword">proc</span> <span class="Identifier">initHashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span> <span class="Operator">=</span>
<span class="Identifier">result</span><span class="Operator">.</span><span class="Identifier">data</span> <span class="Operator">=</span> <span class="Operator">@</span><span class="Punctuation">[</span><span class="Punctuation">]</span>
<span class="Keyword">var</span> <span class="Identifier">tab</span> <span class="Operator">=</span> <span class="Identifier">initHashTable</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">,</span> <span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Identifier">tab</span><span class="Punctuation">[</span><span class="StringLit">"key"</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="StringLit">"abc"</span> <span class="Comment"># calls '[]=' accessor</span>
<span class="Identifier">echo</span> <span class="Identifier">tab</span><span class="Punctuation">[</span><span class="StringLit">"key"</span><span class="Punctuation">]</span> <span class="Comment"># calls '[]' accessor</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_14')">Select</button>
</div>
<div class="slide">
<h1 id="accessors">Accessors</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
</pre></td><td><pre id="listing_15" class="listing"><span class="Keyword">type</span>
<span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="Keyword">object</span>
<span class="Identifier">data</span><span class="Punctuation">:</span> <span class="Identifier">seq</span><span class="Punctuation">[</span><span class="Punctuation">(</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">)</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Identifier">hash</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">K</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">int</span> <span class="Operator">=</span> <span class="DecNumber">0</span>
<span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Punctuation">[</span><span class="Punctuation">]</span><span class="Punctuation">`</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">;</span> <span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">K</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">V</span> <span class="Operator">=</span>
<span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">x</span><span class="Operator">.</span><span class="Identifier">data</span><span class="Punctuation">[</span><span class="Identifier">hash</span><span class="Punctuation">(</span><span class="Identifier">k</span><span class="Punctuation">)</span><span class="Punctuation">]</span><span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Punctuation">[</span><span class="Punctuation">]</span><span class="Operator">=</span><span class="Punctuation">`</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">;</span> <span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">v</span><span class="Punctuation">:</span> <span class="Identifier">V</span><span class="Punctuation">)</span> <span class="Operator">=</span>
<span class="Identifier">x</span><span class="Operator">.</span><span class="Identifier">data</span><span class="Punctuation">[</span><span class="Identifier">hash</span><span class="Punctuation">(</span><span class="Identifier">k</span><span class="Punctuation">)</span><span class="Punctuation">]</span><span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="Identifier">v</span>
<span class="Keyword">proc</span> <span class="Identifier">initHashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">K</span><span class="Punctuation">,</span> <span class="Identifier">V</span><span class="Punctuation">]</span> <span class="Operator">=</span>
<span class="Identifier">result</span><span class="Operator">.</span><span class="Identifier">data</span> <span class="Operator">=</span> <span class="Operator">@</span><span class="Punctuation">[</span><span class="Punctuation">]</span>
<span class="Keyword">var</span> <span class="Identifier">tab</span> <span class="Operator">=</span> <span class="Identifier">initHashTable</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">,</span> <span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Identifier">tab</span><span class="Punctuation">[</span><span class="StringLit">"key"</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span class="StringLit">"abc"</span> <span class="Comment"># calls '[]=' accessor</span>
<span class="Identifier">echo</span> <span class="Identifier">tab</span><span class="Punctuation">[</span><span class="StringLit">"key"</span><span class="Punctuation">]</span> <span class="Comment"># calls '[]' accessor</span>
<span class="Comment"># ouch:</span>
<span class="Identifier">tab</span><span class="Punctuation">[</span><span class="StringLit">"key"</span><span class="Punctuation">]</span><span class="Operator">.</span><span class="Identifier">add</span> <span class="StringLit">"xyz"</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_15')">Select</button>
</div>
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<h1 id="accessors">Accessors</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
</pre></td><td><pre id="listing_16" class="listing"><span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Punctuation">[</span><span class="Punctuation">]</span><span class="Punctuation">`</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">Key</span><span class="Punctuation">,</span> <span class="Identifier">Value</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">HashTable</span><span class="Punctuation">[</span><span class="Identifier">Key</span><span class="Punctuation">,</span> <span class="Identifier">Value</span><span class="Punctuation">]</span><span class="Punctuation">;</span> <span class="Identifier">k</span><span class="Punctuation">:</span> <span class="Identifier">Key</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">Value</span> <span class="Operator">=</span>
<span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">x</span><span class="Operator">.</span><span class="Identifier">data</span><span class="Punctuation">[</span><span class="Identifier">hash</span><span class="Punctuation">(</span><span class="Identifier">key</span><span class="Punctuation">)</span><span class="Punctuation">]</span>
<span class="Keyword">var</span>
<span class="Identifier">tab</span> <span class="Operator">=</span> <span class="Identifier">initHashTable</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">,</span> <span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Comment"># compiles :-)</span>
<span class="Identifier">tab</span><span class="Punctuation">[</span><span class="StringLit">"key"</span><span class="Punctuation">]</span><span class="Operator">.</span><span class="Identifier">add</span> <span class="StringLit">"xyz"</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_16')">Select</button><ul class="simple"><li><tt class="docutils literal"><span class="pre">var</span></tt> "pass by reference" for parameters</li>
<li>can also by used for return values</li>
</ul>
</div>
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<h1 id="distinct">Distinct</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
10
</pre></td><td><pre id="listing_17" class="listing"><span class="Comment"># Taken from system.nim</span>
<span class="Keyword">const</span> <span class="Identifier">taintMode</span> <span class="Operator">=</span> <span class="Identifier">compileOption</span><span class="Punctuation">(</span><span class="StringLit">"taintmode"</span><span class="Punctuation">)</span>
<span class="Keyword">when</span> <span class="Identifier">taintMode</span><span class="Punctuation">:</span>
<span class="Keyword">type</span> <span class="Identifier">TaintedString</span><span class="Operator">*</span> <span class="Operator">=</span> <span class="Keyword">distinct</span> <span class="Identifier">string</span>
<span class="Keyword">proc</span> <span class="Identifier">len</span><span class="Operator">*</span><span class="Punctuation">(</span><span class="Identifier">s</span><span class="Punctuation">:</span> <span class="Identifier">TaintedString</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">int</span> <span class="Punctuation">{</span><span class="Operator">.</span><span class="Identifier">borrow</span><span class="Operator">.</span><span class="Punctuation">}</span>
<span class="Keyword">else</span><span class="Punctuation">:</span>
<span class="Keyword">type</span> <span class="Identifier">TaintedString</span><span class="Operator">*</span> <span class="Operator">=</span> <span class="Identifier">string</span>
<span class="Keyword">proc</span> <span class="Identifier">readLine</span><span class="Operator">*</span><span class="Punctuation">(</span><span class="Identifier">f</span><span class="Punctuation">:</span> <span class="Identifier">File</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">TaintedString</span> <span class="Punctuation">{</span><span class="Operator">.</span><span class="Identifier">tags</span><span class="Punctuation">:</span> <span class="Punctuation">[</span><span class="Identifier">ReadIOEffect</span><span class="Punctuation">]</span><span class="Punctuation">,</span> <span class="Identifier">benign</span><span class="Operator">.</span><span class="Punctuation">}</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_17')">Select</button>
</div>
<div class="slide">
<h1 id="distinct">Distinct</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
</pre></td><td><pre id="listing_18" class="listing"><span class="Comment"># taintmode_ex</span>
<span class="Identifier">echo</span> <span class="Identifier">readLine</span><span class="Punctuation">(</span><span class="Identifier">stdin</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_18')">Select</button><pre>nim c -r --taintMode:on taintmode_ex</pre>
</div>
<div class="slide">
<h1 id="distinct">Distinct</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
</pre></td><td><pre id="listing_19" class="listing"><span class="Comment"># taintmode_ex</span>
<span class="Identifier">echo</span> <span class="Identifier">readLine</span><span class="Punctuation">(</span><span class="Identifier">stdin</span><span class="Punctuation">)</span><span class="Operator">.</span><span class="Identifier">string</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_19')">Select</button><pre>nim c -r --taintMode:on taintmode_ex</pre>
</div>
<div class="slide">
<h1 id="distinct">Distinct</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
</pre></td><td><pre id="listing_20" class="listing"><span class="Comment"># taintmode_ex</span>
<span class="Keyword">proc</span> <span class="Punctuation">`</span><span class="Operator">$</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">TaintedString</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">string</span> <span class="Punctuation">{</span><span class="Operator">.</span><span class="Identifier">borrow</span><span class="Operator">.</span><span class="Punctuation">}</span> <span class="Comment"># but: defeats the purpose</span>
<span class="Identifier">echo</span> <span class="Identifier">readLine</span><span class="Punctuation">(</span><span class="Identifier">stdin</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_20')">Select</button><pre>nim c -r --taintMode:on taintmode_ex</pre>
</div>
<div class="slide">
<h1 id="module-system">Module system</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
</pre></td><td><pre id="listing_21" class="listing"><span class="Comment"># Module A</span>
<span class="Keyword">var</span>
<span class="Identifier">global</span><span class="Operator">*:</span> <span class="Identifier">string</span> <span class="Operator">=</span> <span class="StringLit">"A.global"</span>
<span class="Keyword">proc</span> <span class="Identifier">p</span><span class="Operator">*</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">string</span><span class="Punctuation">)</span> <span class="Operator">=</span> <span class="Identifier">echo</span> <span class="StringLit">"exported "</span><span class="Punctuation">,</span> <span class="Identifier">x</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_21')">Select</button><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
</pre></td><td><pre id="listing_22" class="listing"><span class="Comment"># Module B</span>
<span class="Keyword">import</span> <span class="Identifier">A</span>
<span class="Identifier">echo</span> <span class="Identifier">p</span><span class="Punctuation">(</span><span class="Identifier">global</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_22')">Select</button>
</div>
<div class="slide">
<h1 id="module-system">Module system</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
</pre></td><td><pre id="listing_23" class="listing"><span class="Comment"># Module A</span>
<span class="Keyword">var</span>
<span class="Identifier">global</span><span class="Operator">*:</span> <span class="Identifier">string</span> <span class="Operator">=</span> <span class="StringLit">"A.global"</span>
<span class="Keyword">proc</span> <span class="Identifier">p</span><span class="Operator">*</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">string</span><span class="Punctuation">)</span> <span class="Operator">=</span> <span class="Identifier">echo</span> <span class="StringLit">"exported "</span><span class="Punctuation">,</span> <span class="Identifier">x</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_23')">Select</button><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
</pre></td><td><pre id="listing_24" class="listing"><span class="Comment"># Module B</span>
<span class="Keyword">from</span> <span class="Identifier">A</span> <span class="Keyword">import</span> <span class="Identifier">p</span>
<span class="Identifier">echo</span> <span class="Identifier">p</span><span class="Punctuation">(</span><span class="Identifier">A</span><span class="Operator">.</span><span class="Identifier">global</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_24')">Select</button>
</div>
<div class="slide">
<h1 id="module-system">Module system</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
</pre></td><td><pre id="listing_25" class="listing"><span class="Comment"># Module A</span>
<span class="Keyword">var</span>
<span class="Identifier">global</span><span class="Operator">*:</span> <span class="Identifier">string</span> <span class="Operator">=</span> <span class="StringLit">"A.global"</span>
<span class="Keyword">proc</span> <span class="Identifier">p</span><span class="Operator">*</span><span class="Punctuation">(</span><span class="Identifier">x</span><span class="Punctuation">:</span> <span class="Identifier">string</span><span class="Punctuation">)</span> <span class="Operator">=</span> <span class="Identifier">echo</span> <span class="StringLit">"exported "</span><span class="Punctuation">,</span> <span class="Identifier">x</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_25')">Select</button><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
</pre></td><td><pre id="listing_26" class="listing"><span class="Comment"># Module B</span>
<span class="Keyword">import</span> <span class="Identifier">A</span> <span class="Keyword">except</span> <span class="Identifier">global</span>
<span class="Identifier">echo</span> <span class="Identifier">p</span><span class="Punctuation">(</span><span class="Identifier">A</span><span class="Operator">.</span><span class="Identifier">global</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_26')">Select</button>
</div>
<div class="slide">
<h1 id="routines">Routines</h1><ul class="simple"><li><tt class="docutils literal"><span class="pre">proc</span></tt></li>
<li><tt class="docutils literal"><span class="pre">iterator</span></tt></li>
<li><tt class="docutils literal"><span class="pre">template</span></tt></li>
<li><tt class="docutils literal"><span class="pre">macro</span></tt></li>
<li><tt class="docutils literal"><span class="pre">method</span></tt></li>
<li><tt class="docutils literal"><span class="pre">converter</span></tt></li>
<li>(<tt class="docutils literal"><span class="pre">func</span></tt>)</li>
</ul>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
</pre></td><td><pre id="listing_27" class="listing"><span class="Keyword">iterator</span> <span class="Punctuation">`</span><span class="Operator">..<</span><span class="Punctuation">`</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Punctuation">,</span> <span class="Identifier">b</span><span class="Punctuation">:</span> <span class="Identifier">int</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">int</span> <span class="Operator">=</span>
<span class="Keyword">var</span> <span class="Identifier">i</span> <span class="Operator">=</span> <span class="Identifier">a</span>
<span class="Keyword">while</span> <span class="Identifier">i</span> <span class="Operator"><</span> <span class="Identifier">b</span><span class="Punctuation">:</span>
<span class="Keyword">yield</span> <span class="Identifier">i</span>
<span class="Identifier">i</span> <span class="Operator">+=</span> <span class="DecNumber">1</span>
<span class="Keyword">for</span> <span class="Identifier">i</span> <span class="Keyword">in</span> <span class="FloatNumber">0.</span><span class="Operator">.<</span><span class="DecNumber">10</span><span class="Punctuation">:</span>
<span class="Identifier">echo</span> <span class="Identifier">i</span><span class="Operator">+</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="StringLit">"-th iteration"</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_27')">Select</button>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
</pre></td><td><pre id="listing_28" class="listing"><span class="Keyword">for</span> <span class="Identifier">x</span> <span class="Keyword">in</span> <span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">]</span><span class="Punctuation">:</span>
<span class="Identifier">echo</span> <span class="Identifier">x</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_28')">Select</button>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
</pre></td><td><pre id="listing_29" class="listing"><span class="Keyword">for</span> <span class="Identifier">x</span> <span class="Keyword">in</span> <span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">]</span><span class="Punctuation">:</span>
<span class="Identifier">echo</span> <span class="Identifier">x</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_29')">Select</button><p>Rewritten to:</p>
<table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
</pre></td><td><pre id="listing_30" class="listing"><span class="Keyword">for</span> <span class="Identifier">x</span> <span class="Keyword">in</span> <span class="Identifier">items</span><span class="Punctuation">(</span><span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">]</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Identifier">echo</span> <span class="Identifier">x</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_30')">Select</button>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
</pre></td><td><pre id="listing_31" class="listing"><span class="Keyword">iterator</span> <span class="Identifier">items</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">IX</span><span class="Punctuation">,</span> <span class="Identifier">T</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Punctuation">:</span> <span class="Identifier">array</span><span class="Punctuation">[</span><span class="Identifier">IX</span><span class="Punctuation">,</span> <span class="Identifier">T</span><span class="Punctuation">]</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">T</span> <span class="Punctuation">{</span><span class="Operator">.</span><span class="Identifier">inline</span><span class="Operator">.</span><span class="Punctuation">}</span> <span class="Operator">=</span>
<span class="Keyword">var</span> <span class="Identifier">i</span> <span class="Operator">=</span> <span class="Identifier">low</span><span class="Punctuation">(</span><span class="Identifier">IX</span><span class="Punctuation">)</span>
<span class="Keyword">while</span> <span class="Identifier">i</span> <span class="Operator"><=</span> <span class="Identifier">high</span><span class="Punctuation">(</span><span class="Identifier">IX</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Keyword">yield</span> <span class="Identifier">a</span><span class="Punctuation">[</span><span class="Identifier">i</span><span class="Punctuation">]</span>
<span class="Identifier">i</span> <span class="Operator">+=</span> <span class="DecNumber">1</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_31')">Select</button>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
</pre></td><td><pre id="listing_32" class="listing"><span class="Keyword">for</span> <span class="Identifier">x</span> <span class="Keyword">in</span> <span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">]</span><span class="Punctuation">:</span>
<span class="Identifier">x</span> <span class="Operator">=</span> <span class="DecNumber">0</span> <span class="Comment"># doesn't compile</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_32')">Select</button>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
</pre></td><td><pre id="listing_33" class="listing"><span class="Keyword">var</span> <span class="Identifier">a</span> <span class="Operator">=</span> <span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">]</span>
<span class="Keyword">for</span> <span class="Identifier">x</span> <span class="Keyword">in</span> <span class="Identifier">a</span><span class="Punctuation">:</span>
<span class="Identifier">x</span> <span class="Operator">=</span> <span class="DecNumber">0</span> <span class="Comment"># doesn't compile</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_33')">Select</button>
</div>
<div class="slide">
<h1 id="iterators">Iterators</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
10
11
</pre></td><td><pre id="listing_34" class="listing"><span class="Keyword">iterator</span> <span class="Identifier">mitems</span><span class="Operator">*</span><span class="Punctuation">[</span><span class="Identifier">IX</span><span class="Punctuation">,</span> <span class="Identifier">T</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">array</span><span class="Punctuation">[</span><span class="Identifier">IX</span><span class="Punctuation">,</span> <span class="Identifier">T</span><span class="Punctuation">]</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Keyword">var</span> <span class="Identifier">T</span> <span class="Punctuation">{</span><span class="Operator">.</span><span class="Identifier">inline</span><span class="Operator">.</span><span class="Punctuation">}</span> <span class="Operator">=</span>
<span class="Keyword">var</span> <span class="Identifier">i</span> <span class="Operator">=</span> <span class="Identifier">low</span><span class="Punctuation">(</span><span class="Identifier">IX</span><span class="Punctuation">)</span>
<span class="Keyword">if</span> <span class="Identifier">i</span> <span class="Operator"><=</span> <span class="Identifier">high</span><span class="Punctuation">(</span><span class="Identifier">IX</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Keyword">while</span> <span class="Identifier">true</span><span class="Punctuation">:</span>
<span class="Keyword">yield</span> <span class="Identifier">a</span><span class="Punctuation">[</span><span class="Identifier">i</span><span class="Punctuation">]</span>
<span class="Keyword">if</span> <span class="Identifier">i</span> <span class="Operator">>=</span> <span class="Identifier">high</span><span class="Punctuation">(</span><span class="Identifier">IX</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Keyword">break</span>
<span class="Identifier">i</span> <span class="Operator">+=</span> <span class="DecNumber">1</span>
<span class="Keyword">var</span> <span class="Identifier">a</span> <span class="Operator">=</span> <span class="Punctuation">[</span><span class="DecNumber">1</span><span class="Punctuation">,</span> <span class="DecNumber">2</span><span class="Punctuation">,</span> <span class="DecNumber">3</span><span class="Punctuation">]</span>
<span class="Keyword">for</span> <span class="Identifier">x</span> <span class="Keyword">in</span> <span class="Identifier">mitems</span><span class="Punctuation">(</span><span class="Identifier">a</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Identifier">x</span> <span class="Operator">=</span> <span class="DecNumber">0</span> <span class="Comment"># compiles</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_34')">Select</button>
</div>
<div class="slide">
<h1 id="parallelism">Parallelism</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
</pre></td><td><pre id="listing_35" class="listing"><span class="Keyword">import</span> <span class="Identifier">tables</span><span class="Punctuation">,</span> <span class="Identifier">strutils</span>
<span class="Keyword">proc</span> <span class="Identifier">countWords</span><span class="Punctuation">(</span><span class="Identifier">filename</span><span class="Punctuation">:</span> <span class="Identifier">string</span><span class="Punctuation">)</span><span class="Punctuation">:</span> <span class="Identifier">CountTableRef</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">]</span> <span class="Operator">=</span>
<span class="Comment">## Counts all the words in the file.</span>
<span class="Identifier">result</span> <span class="Operator">=</span> <span class="Identifier">newCountTable</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Keyword">for</span> <span class="Identifier">word</span> <span class="Keyword">in</span> <span class="Identifier">readFile</span><span class="Punctuation">(</span><span class="Identifier">filename</span><span class="Punctuation">)</span><span class="Operator">.</span><span class="Identifier">split</span><span class="Punctuation">:</span>
<span class="Identifier">result</span><span class="Operator">.</span><span class="Identifier">inc</span> <span class="Identifier">word</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_35')">Select</button>
</div>
<div class="slide">
<h1 id="parallelism">Parallelism</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
10
11
12
13
14
</pre></td><td><pre id="listing_36" class="listing"><span class="Comment">#</span>
<span class="Comment">#</span>
<span class="Keyword">const</span>
<span class="Identifier">files</span> <span class="Operator">=</span> <span class="Punctuation">[</span><span class="StringLit">"data1.txt"</span><span class="Punctuation">,</span> <span class="StringLit">"data2.txt"</span><span class="Punctuation">,</span> <span class="StringLit">"data3.txt"</span><span class="Punctuation">,</span> <span class="StringLit">"data4.txt"</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Identifier">main</span><span class="Punctuation">(</span><span class="Punctuation">)</span> <span class="Operator">=</span>
<span class="Keyword">var</span> <span class="Identifier">tab</span> <span class="Operator">=</span> <span class="Identifier">newCountTable</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Keyword">for</span> <span class="Identifier">f</span> <span class="Keyword">in</span> <span class="Identifier">files</span><span class="Punctuation">:</span>
<span class="Keyword">let</span> <span class="Identifier">tab2</span> <span class="Operator">=</span> <span class="Identifier">countWords</span><span class="Punctuation">(</span><span class="Identifier">f</span><span class="Punctuation">)</span>
<span class="Identifier">tab</span><span class="Operator">.</span><span class="Identifier">merge</span><span class="Punctuation">(</span><span class="Identifier">tab2</span><span class="Punctuation">)</span>
<span class="Identifier">tab</span><span class="Operator">.</span><span class="Identifier">sort</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Identifier">echo</span> <span class="Identifier">tab</span><span class="Operator">.</span><span class="Identifier">largest</span>
<span class="Identifier">main</span><span class="Punctuation">(</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_36')">Select</button>
</div>
<div class="slide">
<h1 id="parallelism">Parallelism</h1><table class="line-nums-table"><tbody><tr><td class="blob-line-nums"><pre class="line-nums">1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
</pre></td><td><pre id="listing_37" class="listing"><span class="Keyword">import</span> <span class="Identifier">threadpool</span>
<span class="Keyword">const</span>
<span class="Identifier">files</span> <span class="Operator">=</span> <span class="Punctuation">[</span><span class="StringLit">"data1.txt"</span><span class="Punctuation">,</span> <span class="StringLit">"data2.txt"</span><span class="Punctuation">,</span> <span class="StringLit">"data3.txt"</span><span class="Punctuation">,</span> <span class="StringLit">"data4.txt"</span><span class="Punctuation">]</span>
<span class="Keyword">proc</span> <span class="Identifier">main</span><span class="Punctuation">(</span><span class="Punctuation">)</span> <span class="Operator">=</span>
<span class="Keyword">var</span> <span class="Identifier">tab</span> <span class="Operator">=</span> <span class="Identifier">newCountTable</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Keyword">var</span> <span class="Identifier">results</span><span class="Punctuation">:</span> <span class="Identifier">array</span><span class="Punctuation">[</span><span class="Identifier">files</span><span class="Operator">.</span><span class="Identifier">len</span><span class="Punctuation">,</span> <span style="background-color:#FF7700"><span class="Identifier">FlowVar</span><span class="Punctuation">[</span><span class="Identifier">CountTableRef</span><span class="Punctuation">[</span><span class="Identifier">string</span><span class="Punctuation">]</span><span class="Punctuation">]</span></span><span class="Punctuation">]</span>
<span class="Keyword">for</span> <span class="Identifier">i</span><span class="Punctuation">,</span> <span class="Identifier">f</span> <span class="Keyword">in</span> <span class="Identifier">files</span><span class="Punctuation">:</span>
<span class="Identifier">results</span><span class="Punctuation">[</span><span class="Identifier">i</span><span class="Punctuation">]</span> <span class="Operator">=</span> <span style="background-color:#FF7700"><span class="Identifier">spawn</span></span> <span class="Identifier">countWords</span><span class="Punctuation">(</span><span class="Identifier">f</span><span class="Punctuation">)</span>
<span class="Keyword">for</span> <span class="Identifier">i</span> <span class="Keyword">in</span> <span class="FloatNumber">0.</span><span class="Operator">.</span><span class="Identifier">high</span><span class="Punctuation">(</span><span class="Identifier">results</span><span class="Punctuation">)</span><span class="Punctuation">:</span>
<span class="Identifier">tab</span><span class="Operator">.</span><span class="Identifier">merge</span><span class="Punctuation">(</span><span style="background-color:#FF7700"> <span class="Operator">^</span><span class="Identifier">results</span><span class="Punctuation">[</span><span class="Identifier">i</span><span class="Punctuation">]</span> </span><span class="Punctuation">)</span>
<span class="Identifier">tab</span><span class="Operator">.</span><span class="Identifier">sort</span><span class="Punctuation">(</span><span class="Punctuation">)</span>
<span class="Identifier">echo</span> <span class="Identifier">tab</span><span class="Operator">.</span><span class="Identifier">largest</span>
<span class="Identifier">main</span><span class="Punctuation">(</span><span class="Punctuation">)</span></pre></td></tr></tbody></table><button onclick="copyToClipboard('listing_37')">Select</button>
</body>
</div>
</html>