34 lines
748 B
Crystal
34 lines
748 B
Crystal
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require "./tree.cr"
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module Chalk
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class ConstantFolder < Transformer
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private def perform_op(op, left, right)
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case op
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when TokenType::OpAdd
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left + right
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when TokenType::OpSub
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left - right
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when TokenType::OpMul
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left*right
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when TokenType::OpDiv
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left/right
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when TokenType::OpAnd
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left & right
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when TokenType::OpOr
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left | right
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else TokenType::OpXor
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left ^ right
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end
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end
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def transform(tree : TreeOp)
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if tree.left.is_a?(TreeLit) && tree.right.is_a?(TreeLit)
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return TreeLit.new perform_op(tree.op,
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tree.left.as(TreeLit).lit,
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tree.right.as(TreeLit).lit)
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end
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return tree
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end
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end
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end
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