M.V. Hutz
d715d38e9e
- Rename pkg/interpreter to pkg/runtime - Move ReduceOnce to new pkg/normalorder package - Convert standalone functions (Substitute, Rename, GetFree, IsFree) to receiver methods on concrete expression types - Change Set from pointer receivers to value receivers - Update all references from interpreter to runtime terminology Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
35 lines
781 B
Go
35 lines
781 B
Go
package normalorder
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import "git.maximhutz.com/max/lambda/pkg/lambda"
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func ReduceOnce(e lambda.Expression) (lambda.Expression, bool) {
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switch e := e.(type) {
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case lambda.Abstraction:
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body, reduced := ReduceOnce(e.Body())
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if reduced {
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return lambda.NewAbstraction(e.Parameter(), body), true
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}
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return e, false
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case lambda.Application:
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if fn, fnOk := e.Abstraction().(lambda.Abstraction); fnOk {
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return fn.Body().Substitute(fn.Parameter(), e.Argument()), true
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}
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abs, reduced := ReduceOnce(e.Abstraction())
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if reduced {
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return lambda.NewApplication(abs, e.Argument()), true
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}
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arg, reduced := ReduceOnce(e.Argument())
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if reduced {
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return lambda.NewApplication(e.Abstraction(), arg), true
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}
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return e, false
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default:
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return e, false
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}
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}
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