From a1a709495ea64963fddf7d91e1ce4ff0db7d31b8 Mon Sep 17 00:00:00 2001
From: Mike Perham <mperham@gmail.com>
Date: Tue, 24 May 2016 16:07:11 -0700
Subject: [PATCH] Change default float format

The current format is lossy in the extreme.  This prints the Float as-is with 8 digits of precision.

```
float = Time.now.epoch_f
p float.to_json

str = String.new(22) do |buffer|
  LibC.snprintf(buffer, 22, "%.8f", float)
  len = LibC.strlen(buffer)
  {len, len}
end
p str
```

$ crystal tmp.cr
"1.46413e+09"
"1464131025.34958601"

Does the size 22 constant need to be adjusted?
---
 src/float.cr | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/float.cr b/src/float.cr
index baa67b0c4f12..b18948996182 100644
--- a/src/float.cr
+++ b/src/float.cr
@@ -192,7 +192,7 @@ struct Float64
 
   def to_s
     String.new(22) do |buffer|
-      LibC.snprintf(buffer, 22, "%g", self)
+      LibC.snprintf(buffer, 22, "%.8f", self)
       len = LibC.strlen(buffer)
       {len, len}
     end
@@ -200,7 +200,7 @@ struct Float64
 
   def to_s(io : IO)
     chars = StaticArray(UInt8, 22).new(0_u8)
-    LibC.snprintf(chars, 22, "%g", self)
+    LibC.snprintf(chars, 22, "%.8f", self)
     io.write_utf8 chars.to_slice[0, LibC.strlen(chars)]
   end