Add boolean literals

grammar.js

@@ -34,6 +34,7 @@ module.exports = grammar({
     _expr: ($) => choice(
       // Literals
       $.identifier,
+      $.boolean_literal,
       $.integer_literal,
       $._string_literal,
       // Composites
@@ -44,6 +45,8 @@ module.exports = grammar({
     // The Blueprint scanner makes use of Go's lexer, so copy their rule
     identifier: (_) => /[_\p{XID_Start}][_\p{XID_Continue}]*/,
 
+    boolean_literal: (_) => choice("true", "false"),
+
     integer_literal: (_) => seq(optional("-"), /[0-9]+/),
 
     // The Blueprint scanner makes use of Go's lexer, so copy their rule

src/grammar.json

@@ -75,6 +75,10 @@
           "type": "SYMBOL",
           "name": "identifier"
         },
+        {
+          "type": "SYMBOL",
+          "name": "boolean_literal"
+        },
         {
           "type": "SYMBOL",
           "name": "integer_literal"
@@ -97,6 +101,19 @@
       "type": "PATTERN",
       "value": "[_\\p{XID_Start}][_\\p{XID_Continue}]*"
     },
+    "boolean_literal": {
+      "type": "CHOICE",
+      "members": [
+        {
+          "type": "STRING",
+          "value": "true"
+        },
+        {
+          "type": "STRING",
+          "value": "false"
+        }
+      ]
+    },
     "integer_literal": {
       "type": "SEQ",
       "members": [

src/node-types.json

@@ -31,6 +31,10 @@
         "multiple": false,
         "required": true,
         "types": [
+          {
+            "type": "boolean_literal",
+            "named": true
+          },
           {
             "type": "identifier",
             "named": true
@@ -59,6 +63,11 @@
       }
     }
   },
+  {
+    "type": "boolean_literal",
+    "named": true,
+    "fields": {}
+  },
   {
     "type": "comment",
     "named": true,
@@ -92,6 +101,10 @@
       "multiple": true,
       "required": false,
       "types": [
+        {
+          "type": "boolean_literal",
+          "named": true
+        },
         {
           "type": "identifier",
           "named": true
@@ -137,6 +150,10 @@
         "multiple": true,
         "required": false,
         "types": [
+          {
+            "type": "boolean_literal",
+            "named": true
+          },
           {
             "type": "identifier",
             "named": true
@@ -220,6 +237,10 @@
     "type": "escape_sequence",
     "named": true
   },
+  {
+    "type": "false",
+    "named": false
+  },
   {
     "type": "identifier",
     "named": true
@@ -228,6 +249,10 @@
     "type": "raw_string_literal",
     "named": true
   },
+  {
+    "type": "true",
+    "named": false
+  },
   {
     "type": "{",
     "named": false

test/corpus/expressions.txt

@@ -1,3 +1,37 @@
+================================================================================
+Boolean
+================================================================================
+
+foo = false
+foo = true
+
+--------------------------------------------------------------------------------
+
+(source_file
+  (assignment
+    (identifier)
+    (boolean_literal))
+  (assignment
+    (identifier)
+    (boolean_literal)))
+
+================================================================================
+Boolean (identifier/literal)
+================================================================================
+
+true = false
+false = true
+
+--------------------------------------------------------------------------------
+
+(source_file
+  (assignment
+    (identifier)
+    (boolean_literal))
+  (assignment
+    (identifier)
+    (boolean_literal)))
+
 ================================================================================
 Integer
 ================================================================================