Add char literals

grammar.coffee

@@ -183,6 +183,7 @@ module.exports = grammar
       @field_access,
       @deref_field_access,
       @number,
+      @char,
       @string)
 
     field_access: -> seq(
@@ -226,6 +227,13 @@ module.exports = grammar
 
     number: -> /\d+(\.\d+)?/
 
+    char: -> token(seq(
+      "'",
+      choice(
+        seq(optional("\\"), /[^']/),
+        seq("\\", "'")),
+      "'"))
+
     string: -> token(seq(
       '"', repeat(choice(/[^"]/, '\\"')), '"'))
 

grammar_test/expressions.txt

@@ -12,6 +12,26 @@ int main() {
   (statement_block
     (expression_statement (function_call (identifier) (string) (identifier)))))
 
+============================================
+Character literals
+============================================
+
+int main() {
+  'a';
+  '\0';
+  '\t';
+  '\'';
+}
+
+---
+
+(function_declaration (identifier) (identifier) (formal_parameters)
+  (statement_block
+    (expression_statement (char))
+    (expression_statement (char))
+    (expression_statement (char))
+    (expression_statement (char))))
+
 ============================================
 Field access
 ============================================