diff options
| -rw-r--r-- | racket.html.markdown | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/racket.html.markdown b/racket.html.markdown index b6c1f86b..adacd91d 100644 --- a/racket.html.markdown +++ b/racket.html.markdown @@ -5,6 +5,7 @@ filename: learnracket.rkt contributors: - ["th3rac25", "https://github.com/voila"] - ["Eli Barzilay", "https://github.com/elibarzilay"] + - ["Gustavo Schmidt", "https://github.com/gustavoschmidt"] --- Racket is a general purpose, multi-paradigm programming language in the Lisp/Scheme family. @@ -555,11 +556,15 @@ vec ; => #(1 2 3 4) (set! x y) (set! y tmp))) -(define tmp 1) -(define a 2) -(define b 3) -(swap! a b) -(printf "tmp = ~a; a = ~a; b = ~a\n" tmp a b) ; tmp is unaffected +(define tmp 2) +(define other 3) +(swap! tmp other) +(printf "tmp = ~a; other = ~a\n" tmp other) +;; The variable `tmp` is renamed to `tmp_1` +;; in order to avoid name conflict +;; (let ([tmp_1 tmp]) +;; (set! tmp other) +;; (set! other tmp_1)) ;; But they are still code transformations, for example: (define-syntax-rule (bad-while condition body ...) |