30 lines
914 B
Ruby
30 lines
914 B
Ruby
module Ast
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class IfExpression < Expression
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# attr_reader :cond, :if_true, :if_false
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def compile method , message
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is = cond.compile(method,message)
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# is.is_false(frame,method)
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# TODO should/will use different branches for different conditions.
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branch = Virtual::ImplicitBranch.new "if_merge"
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method.add_code branch
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last = is
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if_true.each do |part|
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last = part.compile(method,message )
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raise part.inspect if last.nil?
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end
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merge = Virtual::Label.new(branch.name)
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method.add_code merge
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branch.swap
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method.current = branch
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if_false.each do |part|
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last = part.compile(method,message )
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raise part.inspect if last.nil?
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end
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method.add_code merge
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branch.swap
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method.current = merge
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#TODO should return the union of the true and false types
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last
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end
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end
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end |