39 lines
954 B
Ruby
39 lines
954 B
Ruby
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module Virtual
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# static description of a method
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# name
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# args (with defaults)
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# code
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# return arg (usually mystery, but for coded ones can be more specific)
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# known local variable names
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# temp variables (numbered)
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#
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class Method
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#return the main function (the top level) into which code is compiled
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def Method.main
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Method.new(:main)
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end
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def initialize name , args = []
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@name = name
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@args = args
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@locals = []
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@start = MethodEnter.new
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@current = @start
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end
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attr_reader :name
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def add instruction
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@current.next = instruction
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@current = instruction
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end
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# determine whether this method has a variable by the given name
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# variables are locals and and arguments
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# used to determine if a send must be issued
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def has_var name
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var = @args.find {|a| a == name }
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var = @locals.find {|a| a == name } unless var
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var
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end
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end
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end
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