Add function definition syntax

src/abstract_tree/anonymous_function.rs

@@ -53,7 +53,7 @@ impl AnonymousFunction {
 
 impl AbstractTree for AnonymousFunction {
     fn from_syntax(node: SyntaxNode, source: &str, context: &Context) -> Result<Self, SyntaxError> {
-        SyntaxError::expect_syntax_node("function", node)?;
+        SyntaxError::expect_syntax_node("anonymous_function", node)?;
 
         let child_count = node.child_count();
         let mut parameters = Vec::new();

src/abstract_tree/value_node.rs

@@ -38,7 +38,7 @@ impl AbstractTree for ValueNode {
         let value_node = match child.kind() {
             "boolean" => ValueNode::Boolean(source[child.byte_range()].to_string()),
             "float" => ValueNode::Float(source[child.byte_range()].to_string()),
-            "function" => {
+            "anonymous_function" => {
                 let function_node = AnonymousFunction::from_syntax(child, source, context)?;
 
                 ValueNode::Function(Function::ContextDefined(function_node))

tree-sitter-dust/corpus/functions.txt

@@ -247,3 +247,35 @@ from_json(read('file.json'))
               (expression
                 (value
                   (string))))))))))
+
+================================================================================
+Function Definition
+================================================================================
+
+fn foo<T> (bar <T>) <T> {
+  bar
+}
+
+--------------------------------------------------------------------------------
+
+(root
+  (statement
+    (statement_kind
+      (type_definition
+        (function_definition
+          (identifier)
+          (type_arguments
+            (type
+              (identifier)))
+          (identifier)
+          (type_specification
+            (type
+              (identifier)))
+          (type_specification
+            (type
+              (identifier)))
+          (block
+            (statement
+              (statement_kind
+                (expression
+                  (identifier))))))))))

tree-sitter-dust/grammar.js

@@ -478,6 +478,7 @@ module.exports = grammar({
     type_definition: $ =>
       choice(
         $.enum_definition,
+        $.function_definition,
         $.struct_definition,
       ),
 
@@ -555,5 +556,23 @@ module.exports = grammar({
 
     struct_instance: $ =>
       seq($.identifier, '::', $.map),
+
+    function_definition: $ =>
+      seq(
+        'fn',
+        $.identifier,
+        optional($.type_arguments),
+        '(',
+        repeat(
+          seq(
+            $.identifier,
+            $.type_specification,
+            optional(','),
+          ),
+        ),
+        ')',
+        $.type_specification,
+        $.block,
+      ),
   },
 });

tree-sitter-dust/src/grammar.json

@@ -1451,6 +1451,10 @@
           "type": "SYMBOL",
           "name": "enum_definition"
         },
+        {
+          "type": "SYMBOL",
+          "name": "function_definition"
+        },
         {
           "type": "SYMBOL",
           "name": "struct_definition"
@@ -1717,6 +1721,75 @@
           "name": "map"
         }
       ]
+    },
+    "function_definition": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "STRING",
+          "value": "fn"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "identifier"
+        },
+        {
+          "type": "CHOICE",
+          "members": [
+            {
+              "type": "SYMBOL",
+              "name": "type_arguments"
+            },
+            {
+              "type": "BLANK"
+            }
+          ]
+        },
+        {
+          "type": "STRING",
+          "value": "("
+        },
+        {
+          "type": "REPEAT",
+          "content": {
+            "type": "SEQ",
+            "members": [
+              {
+                "type": "SYMBOL",
+                "name": "identifier"
+              },
+              {
+                "type": "SYMBOL",
+                "name": "type_specification"
+              },
+              {
+                "type": "CHOICE",
+                "members": [
+                  {
+                    "type": "STRING",
+                    "value": ","
+                  },
+                  {
+                    "type": "BLANK"
+                  }
+                ]
+              }
+            ]
+          }
+        },
+        {
+          "type": "STRING",
+          "value": ")"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "type_specification"
+        },
+        {
+          "type": "SYMBOL",
+          "name": "block"
+        }
+      ]
     }
   },
   "extras": [

tree-sitter-dust/src/node-types.json

@@ -309,6 +309,33 @@
       ]
     }
   },
+  {
+    "type": "function_definition",
+    "named": true,
+    "fields": {},
+    "children": {
+      "multiple": true,
+      "required": true,
+      "types": [
+        {
+          "type": "block",
+          "named": true
+        },
+        {
+          "type": "identifier",
+          "named": true
+        },
+        {
+          "type": "type_arguments",
+          "named": true
+        },
+        {
+          "type": "type_specification",
+          "named": true
+        }
+      ]
+    }
+  },
   {
     "type": "function_expression",
     "named": true,
@@ -822,6 +849,10 @@
           "type": "enum_definition",
           "named": true
         },
+        {
+          "type": "function_definition",
+          "named": true
+        },
         {
           "type": "struct_definition",
           "named": true
@@ -1074,6 +1105,10 @@
     "type": "float",
     "named": false
   },
+  {
+    "type": "fn",
+    "named": false
+  },
   {
     "type": "for",
     "named": false