Annotations

org.lflang.diagram/src/org/lflang/diagram/synthesis/LinguaFrancaSynthesis.java

@@ -1365,7 +1365,7 @@ private KNode addErrorComment(KNode node, String message) {
 
     private Iterable<KNode> createUserComments(EObject element, KNode targetNode) {
         if (getBooleanValue(SHOW_USER_LABELS)) {
-            String commentText = ASTUtils.findAnnotationInComments(element, "@label");
+            String commentText = ASTUtils.label(element);
 
             if (!StringExtensions.isNullOrEmpty(commentText)) {
                 KNode comment = _kNodeExtensions.createNode();

org.lflang.tests/src/org/lflang/tests/compiler/LinguaFrancaParsingTest.java

@@ -30,6 +30,8 @@
 import org.eclipse.xtext.testing.InjectWith;
 import org.eclipse.xtext.testing.extensions.InjectionExtension;
 import org.eclipse.xtext.testing.util.ParseHelper;
+
+import org.lflang.lf.LfPackage;
 import org.lflang.lf.Model;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Assertions;
@@ -65,4 +67,50 @@ public void checkForTarget() throws Exception {
         Assertions.assertNotNull(result);
         Assertions.assertFalse(result.eResource().getErrors().isEmpty(), "Failed to catch misspelled target keyword.");
     }
-}
+
+    @Test
+    public void testAttributes() throws Exception {
+        String testCase = """
+                target C;
+                @label("somethign", "else")
+                @ohio()
+                @a
+                @bdebd(a="b")
+                @bd("abc")
+                @bd("abc",)
+                @a(a="a", b="b")
+                @a(a="a", b="b",)
+                main reactor {
+
+                }
+            """;
+        parseWithoutError(testCase);
+    }
+
+    @Test
+    public void testAttributeContexts() throws Exception {
+        String testCase = """
+                target C;
+                @a
+                main reactor(@b parm: int) {
+
+                    @ohio reaction() {==}
+                    @ohio logical action f;
+                    @ohio timer t;
+                    @ohio input q: int;
+                    @ohio output q2: int;
+                }
+            """;
+        parseWithoutError(testCase);
+    }
+
+    private Model parseWithoutError(String s) throws Exception {
+        Model model = parser.parse(s);
+        Assertions.assertNotNull(model);
+        Assertions.assertTrue(model.eResource().getErrors().isEmpty(),
+                              "Encountered unexpected error while parsing: " +
+                                  model.eResource().getErrors());
+        return model;
+    }
+
+}

org.lflang.tests/src/org/lflang/tests/compiler/LinguaFrancaValidationTest.java

@@ -2222,6 +2222,30 @@ public void testUnrecognizedTarget() throws Exception {
             "Unrecognized target: Pjthon");
     }
 
+
+    @Test
+    public void testWrongStructureForLabelAttribute() throws Exception {
+        String testCase = """
+                target C;
+                @label(name="something")
+                main reactor { }
+            """;
+        validator.assertError(parseWithoutError(testCase), LfPackage.eINSTANCE.getAttribute(), null,
+            "Unknown attribute parameter.");
+    }
+
+
+    @Test
+    public void testMissingName() throws Exception {
+        String testCase = """
+                target C;
+                @label("something", "else")
+                main reactor { }
+            """;
+        validator.assertError(parseWithoutError(testCase), LfPackage.eINSTANCE.getAttribute(), null,
+            "Missing name for attribute parameter.");
+    }
+
     @Test
     public void testInitialMode() throws Exception {
         String testCase = """

org.lflang/src/org/lflang/ASTUtils.java

@@ -62,6 +62,7 @@
 import org.lflang.lf.Action;
 import org.lflang.lf.ActionOrigin;
 import org.lflang.lf.Assignment;
+import org.lflang.lf.Attribute;
 import org.lflang.lf.Code;
 import org.lflang.lf.Connection;
 import org.lflang.lf.Element;
@@ -1747,16 +1748,73 @@ public static String findAnnotationInComments(EObject object, String key) {
         return null;
     }
 
+    /**
+     * Return the value of the {@code @label} attribute if
+     * present, otherwise return null.
+     *
+     * @throws IllegalArgumentException If the node cannot have attributes
+     */
+    public static String findLabelAttribute(EObject node) {
+        List<Attribute> attrs = getAttributes(node);
+        return attrs.stream()
+                    .filter(it -> it.getAttrName().equals("label"))
+                    .map(it -> it.getAttrParms().get(0).getValue())
+                    .findFirst()
+                    .orElse(null);
+
+    }
+
+    /**
+     * Return the attributes declared on the given node. Throws
+     * if the node does not support declaring attributes.
+     *
+     * @throws IllegalArgumentException If the node cannot have attributes
+     */
+    public static List<Attribute> getAttributes(EObject node) {
+        if (node instanceof Reactor) {
+            return ((Reactor) node).getAttributes();
+        } else if (node instanceof Reaction) {
+            return ((Reaction) node).getAttributes();
+        } else if (node instanceof Action) {
+            return ((Action) node).getAttributes();
+        } else if (node instanceof Timer) {
+            return ((Timer) node).getAttributes();
+        } else if (node instanceof StateVar) {
+            return ((StateVar) node).getAttributes();
+        } else if (node instanceof Parameter) {
+            return ((Parameter) node).getAttributes();
+        } else if (node instanceof Input) {
+            return ((Input) node).getAttributes();
+        } else if (node instanceof Output) {
+            return ((Output) node).getAttributes();
+        }
+        throw new IllegalArgumentException("Not annotatable: " + node);
+    }
+
     /**
      * Search for an `@label` annotation for a given reaction.
-     * 
+     *
      * @param n the reaction for which the label should be searched
      * @return The annotated string if an `@label` annotation was found. `null` otherwise.
      */
     public static String label(Reaction n) {
-        return findAnnotationInComments(n, "@label");
+        return label((EObject) n);
     }
-
+
+    /**
+     * Return the declared label of the node, as given by the @label
+     * annotation (or an @label comment).
+     *
+     * @throws IllegalArgumentException If the node cannot have attributes
+     */
+    public static String label(EObject n) {
+        String fromAttr = findLabelAttribute(n);
+        if (fromAttr == null) {
+            return findAnnotationInComments(n, "@label");
+        }
+        return fromAttr;
+    }
+
     /**
      * Find the main reactor and set its name if none was defined.
      * @param resource The resource to find the main reactor in.

org.lflang/src/org/lflang/LinguaFranca.xtext

@@ -74,7 +74,7 @@ ImportedReactor: reactorClass=[Reactor] ('as' name=ID)?;
  * Declaration of a reactor class.
  */
 Reactor:
-    {Reactor} ((federated?='federated' | main?='main')? & realtime?='realtime'?) 'reactor' (name=ID)? 
+    {Reactor} (attributes+=Attribute)* ((federated?='federated' | main?='main')? & realtime?='realtime'?) 'reactor' (name=ID)?
     ('<' typeParms+=TypeParm (',' typeParms+=TypeParm)* '>')?
     ('(' parameters+=Parameter (',' parameters+=Parameter)* ')')?
     ('at' host=Host)?
@@ -129,6 +129,7 @@ TargetDecl:
  *  must be given, or a literal or code that denotes zero.
  */
  StateVar:
+    (attributes+=Attribute)*
     (reset?='reset')? 'state' name=ID (
         (':' (type=Type))? 
         ((parens+='(' (init+=Expression (','  init+=Expression)*)? parens+=')')
@@ -150,24 +151,24 @@ MethodArgument:
 ;
 
 Input:
-    mutable?='mutable'? 'input' (widthSpec=WidthSpec)? name=ID (':' type=Type)? ';'?;
+    (attributes+=Attribute)* mutable?='mutable'? 'input' (widthSpec=WidthSpec)? name=ID (':' type=Type)? ';'?;
 
 Output:
-    'output' (widthSpec=WidthSpec)? name=ID (':' type=Type)? ';'?;
+    (attributes+=Attribute)* 'output' (widthSpec=WidthSpec)? name=ID (':' type=Type)? ';'?;
 
 // Timing specification for a timer: (offset, period)
 // Can be empty, which means (0,0) = (NOW, ONCE).
 // E.g. (0) or (NOW) or (NOW, ONCE) or (100, 1000)
 // The latter means fire with period 1000, offset 100.
 Timer:
-    'timer' name=ID ('(' offset=Expression (',' period=Expression)? ')')? ';'?;
+   (attributes+=Attribute)* 'timer' name=ID ('(' offset=Expression (',' period=Expression)? ')')? ';'?;
 
 Boolean:
     TRUE | FALSE
 ;
 
 Mode:
-    {Mode} (initial?='initial')? 'mode' (name=ID)? 
+    {Mode} (initial?='initial')? 'mode' (name=ID)?
     '{' (
         (stateVars+=StateVar) |
         (timers+=Timer) |
@@ -188,11 +189,13 @@ Mode:
 // For all actions, minSpacing is the minimum difference between
 // the tags of two subsequently scheduled events.
 Action:
-    (origin=ActionOrigin)? 'action' name=ID 
+    (attributes+=Attribute)*
+    (origin=ActionOrigin)? 'action' name=ID
     ('(' minDelay=Expression (',' minSpacing=Expression (',' policy=STRING)? )? ')')?
     (':' type=Type)? ';'?;
 
 Reaction:
+    (attributes+=Attribute)*
     ('reaction')
     ('(' (triggers+=TriggerRef (',' triggers+=TriggerRef)*)? ')')?
     (sources+=VarRef (',' sources+=VarRef)*)?
@@ -244,6 +247,18 @@ Serializer:
     'serializer' type=STRING
 ;
 
+/////////// Attributes
+Attribute:
+    '@' attrName=ID ('(' (attrParms+=AttrParm (',' attrParms+=AttrParm)* ','?)? ')')?
+;
+
+AttrParm:
+    (name=ID '=')? value=AttrParmValue;
+
+AttrParmValue:
+    STRING
+;
+
 /////////// For target parameters
 
 KeyValuePairs:
@@ -289,6 +304,7 @@ Assignment:
  * Parameter declaration with optional type and mandatory initialization.
  */
 Parameter:
+    (attributes+=Attribute)*
     name=ID (':' (type=Type))?
     ((parens+='(' (init+=Expression (','  init+=Expression)*)? parens+=')')
         | (braces+='{' (init+=Expression (','  init+=Expression)*)? braces+='}')
@@ -510,4 +526,4 @@ Token:
     '@' |
     // Single quotes
     "'"
-;
+;