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diff test/expression.x @ 318:e84047f29c78

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Add burg and yacc initial attempts
author Windel Bouwman
date Tue, 31 Dec 2013 12:38:15 +0100
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/expression.x	Tue Dec 31 12:38:15 2013 +0100
@@ -0,0 +1,16 @@
+
+%tokens '+' number '(' ')' '*'
+%%
+
+input: expression {return $1};
+
+expression: term { return $1 }
+          | expression '+' term {};
+
+term: factor { return $1 }
+    | term '*' factor { return $1 * $3 };
+
+factor: '(' expression ')'
+      | number {return $1.val};
+
+