36 lines
459 B
V
36 lines
459 B
V
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module parser
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import compiler2.ast
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fn test_parser() {
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//expr := ast.IntegerExpr {val:10}
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//expr := ast.BinaryExpr{}
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expr := parse_expr('3 + 7')
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walk(expr)
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println('')
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}
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fn walk(node ast.Expr) {
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//println('walk()')
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match node {
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ast.IntegerExpr {
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print(it.val)
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}
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ast.BinaryExpr {
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walk(it.left)
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match it.op {
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.plus {
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print(' + ')
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}
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.minus {
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print(' - ')
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}
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else {}
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}
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walk(it.right)
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}
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else {}
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}
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}
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