fix: allow "match" on LHS of named_expression (#153)

Fixes #150

Author: theHamsta

grammar.js

@@ -190,11 +190,16 @@ module.exports = grammar({
     ),
 
     named_expression: $ => seq(
-      field('name', $.identifier),
+      field('name', $._named_expresssion_lhs),
       ':=',
       field('value', $.expression)
     ),
 
+    _named_expresssion_lhs: $ => choice(
+      $.identifier,
+      alias('match', $.identifier), // ambiguity with match statement: only ":" at end of line decides if "match" keyword
+    ),
+
     return_statement: $ => seq(
       'return',
       optional($._expressions)
@@ -499,7 +504,7 @@ module.exports = grammar({
 
     pattern: $ => choice(
       $.identifier,
-      alias("match", $.identifier), // ambiguity with match statement: only ":" at end of line decides if "match" keyword
+      alias('match', $.identifier), // ambiguity with match statement: only ":" at end of line decides if "match" keyword
       $.keyword_identifier,
       $.subscript,
       $.attribute,

src/grammar.json

@@ -604,7 +604,7 @@
           "name": "name",
           "content": {
             "type": "SYMBOL",
-            "name": "identifier"
+            "name": "_named_expresssion_lhs"
           }
         },
         {
@@ -621,6 +621,24 @@
         }
       ]
     },
+    "_named_expresssion_lhs": {
+      "type": "CHOICE",
+      "members": [
+        {
+          "type": "SYMBOL",
+          "name": "identifier"
+        },
+        {
+          "type": "ALIAS",
+          "content": {
+            "type": "STRING",
+            "value": "match"
+          },
+          "named": true,
+          "value": "identifier"
+        }
+      ]
+    },
     "return_statement": {
       "type": "SEQ",
       "members": [