proc is a char->char procedure, it is mapped over s. The order in which the procedure is applied to the string elements is not specified.
proc is a char->char procedure, it is mapped over s. The order in which the procedure is applied to the string elements is not specified. The string s is modified in-place, the return value is not specified.
proc is mapped over s in left-to-right order. The return value is not specified.
Call (proc i)
for each index i in s, from left to
right.
For example, to change characters to alternately upper and lower case,
(define str (string-copy "studly")) (string-for-each-index (lambda (i) (string-set! str i ((if (even? i) char-upcase char-downcase) (string-ref str i)))) str) str ⇒ "StUdLy"
Fold kons over the characters of s, with knil as the terminating element, from left to right. kons must expect two arguments: The actual character and the last result of kons’ application.
Fold kons over the characters of s, with knil as the terminating element, from right to left. kons must expect two arguments: The actual character and the last result of kons’ application.
(lambda (x) )
.