13 lines
344 B
Racket
13 lines
344 B
Racket
;there is no built-in way to set! prepend in racket
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(define str "foo")
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(set! str (string-append "bar " str))
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(displayln str)
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;but you can create a quick macro to solve that problem
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(define-syntax-rule (set-prepend! str value)
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(set! str (string-append value str)))
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(define macrostr " bar")
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(set-prepend! macrostr "foo")
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(displayln macrostr)
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