41 lines
1 KiB
Go
41 lines
1 KiB
Go
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package postscript
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func ifoperator(interpreter *Interpreter) {
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operator := NewProcedure(interpreter.PopProcedureDefinition())
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condition := interpreter.PopBoolean()
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if condition {
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operator.Execute(interpreter)
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}
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}
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func ifelse(interpreter *Interpreter) {
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operator2 := NewProcedure(interpreter.PopProcedureDefinition())
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operator1 := NewProcedure(interpreter.PopProcedureDefinition())
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condition := interpreter.PopBoolean()
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if condition {
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operator1.Execute(interpreter)
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} else {
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operator2.Execute(interpreter)
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}
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}
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func foroperator(interpreter *Interpreter) {
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proc := NewProcedure(interpreter.PopProcedureDefinition())
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limit := interpreter.PopFloat()
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inc := interpreter.PopFloat()
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initial := interpreter.PopFloat()
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for i := initial; i <= limit; i += inc {
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interpreter.Push(i)
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proc.Execute(interpreter)
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}
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}
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func initControlOperators(interpreter *Interpreter) {
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interpreter.SystemDefine("if", NewOperator(ifoperator))
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interpreter.SystemDefine("ifelse", NewOperator(ifelse))
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interpreter.SystemDefine("for", NewOperator(foroperator))
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}
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