A toy scheme evaluator implemented by python3, features:
- varible and function
- expression
- lambda expression
- closure
Run evaluator.py：
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Input Expression:
(define x 34)
ok
End Evaluation
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Input Expression:
(+ x 5 7 8)
54
End Evaluation
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Input Expression:
(define (add-six x) (+ x 6))
ok
End Evaluation
--------------------
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Input Expression:
(add-six x)
40
End Evaluation
--------------------