27 lines
958 B
Ruby
27 lines
958 B
Ruby
module SlotMachine
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# A base class for conditions in SlotMachine
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# Checks (if in code, compare in assm) jump or not, depending
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# The logic we choose is closer to the code logic (the asm is reversed)
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# When we write an if, the true is the next code, so the Check logic is
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# that if the check passes, no jump happens
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# This means you need to pass the false label, where to jump to if the
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# check does not pass
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# Note: In assembler a branch on 0 does just that, it branches if the condition
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# is met. This means that the asm implementation is somewhat the reverse
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# of the SlotMachine names. But it's easier to understand (imho)
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class Check < Instruction
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attr_reader :false_label
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def initialize(false_label)
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set_label(false_label)
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end
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def set_label(false_label)
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@false_label = false_label
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raise "Jump target must be a label #{false_label}" unless false_label.is_a?(Label)
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end
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end
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end
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