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Task/String-append/Racket/string-append.rkt

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+;there is no built-in way to set! append in racket
+(define mystr "foo")
+(set! mystr (string-append mystr " bar"))
+(displayln mystr)
+
+;but you can create a quick macro to solve that problem
+(define-syntax-rule (set-append! str value)
+  (set! str (string-append str value)))
+
+(define mymacrostr "foo")
+(set-append! mymacrostr " bar")
+(displayln mystr)