Add var declarations

grammar.coffee

@@ -15,7 +15,8 @@ module.exports = compiler.grammar
       @if_statement,
       @for_statement,
       @statement_block,
-      @return_statement)
+      @return_statement,
+      @var_declaration)
 
     expression_statement: -> seq(
       optional(@expression), ";")
@@ -39,6 +40,16 @@ module.exports = compiler.grammar
       optional(@expression),
       ";")
 
+    var_declaration: -> seq(
+      keyword("var"),
+      commaSep(choice(
+        @identifier,
+        seq(
+          @identifier,
+          "=",
+          @expression))),
+      ";")
+
     expression: -> choice(
       @identifier,
       @number,

grammar_test/statements.txt

@@ -61,3 +61,19 @@ return 5;
 (program
   (return_statement)
   (return_statement (number)))
+
+============================================
+Var declarations
+============================================
+
+var x = 1;
+var x, y = {}, z;
+
+---
+
+(program
+  (var_declaration (identifier) (number))
+  (var_declaration
+    (identifier)
+    (identifier) (object)
+    (identifier)))