Programming-Idioms

Edit summary for version 115 by programming-idioms.org:
Restored version 113

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2020-04-28, 19:31:52

2020-04-30, 20:08:37

Idiom #12 Check if list contains a value

Check if list contains a value x.
list is an iterable finite container.

Check if list contains a value x.
list is an iterable finite container.

array vector member membership

array vector member membership

(define (f i lst)
   (if (= i 0) (car lst)
       (f (- i 1) (cdr lst))))

(define (contains list x)
        (if (null? list) #f)
        (if (equal? (car list) x) #t)
        (else (contains (cdr list) x))))

This is a custom implementation, use it if no built-in predicate is available in your Scheme environment.

This is a custom implementation, use it if no built-in predicate is available in your Scheme environment.

http://repl.it/SIT

http://repl.it/SIT

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