24 lines
448 B
Go
24 lines
448 B
Go
package lambda
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func ReduceOnce(e *Expression) bool {
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switch typed := (*e).(type) {
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case *Abstraction:
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return ReduceOnce(&typed.Body)
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case *Application:
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fn, fn_ok := typed.Abstraction.(*Abstraction)
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if fn_ok {
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Substitute(&fn.Body, fn.Parameter, typed.Argument)
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*e = fn.Body
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return true
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}
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good := ReduceOnce(&typed.Abstraction)
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if good {
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return true
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}
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return ReduceOnce(&typed.Argument)
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default:
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return false
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}
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}
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