37 lines
1.0 KiB
Ruby
37 lines
1.0 KiB
Ruby
module SlotMachine
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# The funny thing about the ruby truth is that it is anything but false or nil
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#
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# To implement the normal ruby logic, we check for false or nil and jump
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# to the false branch. true_block follows implicitly
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#
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class TruthCheck < Check
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attr_reader :condition
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def initialize(condition , false_label)
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super(false_label)
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@condition = condition
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raise "condition must be slot_definition #{condition}" unless condition.is_a?(Slotted)
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end
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def to_s
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"TruthCheck #{@condition} -> #{false_label}"
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end
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def to_risc(compiler)
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false_label = @false_label.risc_label(compiler)
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condition_reg = @condition.to_register(compiler,self)
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compiler.build(self.to_s) do
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object = load_object Parfait.object_space.false_object
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object.op :- , condition_reg
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if_zero false_label
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object = load_object Parfait.object_space.nil_object
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object.op :- , condition_reg
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if_zero false_label
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end
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end
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end
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end
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