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39 lines
1.1 KiB
Racket
39 lines
1.1 KiB
Racket
#lang br/quicklang
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(define (read-syntax path port)
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(define args (port->lines port))
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(define handle-datums (format-datums '(handle ~a) args))
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(define module-datum `(module stacker-mod stacker-demo/stacker
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,@handle-datums))
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(datum->syntax #f module-datum))
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(provide read-syntax)
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(define-macro (stacker-module-begin HANDLE-EXPR ...)
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#'(#%module-begin
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HANDLE-EXPR ...
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(display (first stack))))
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(provide (rename-out [stacker-module-begin #%module-begin]))
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(define stack empty)
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(define (pop-stack!)
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(define arg (first stack))
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(set! stack (rest stack))
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arg)
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(define (push-stack! arg)
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(set! stack (cons arg stack)))
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(define (handle [arg #f])
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(cond
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[(number? arg) (push-stack! arg)]
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[(or (equal? * arg) (equal? + arg))
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; This will ensure that stacker can be extended to support - and / operations while keeping the RPN notation
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(define operand2 (pop-stack!))
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(define operand1 (pop-stack!))
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(define op-result (arg operand1 operand2))
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(push-stack! op-result)]))
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(provide handle)
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(provide + *)
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