chickadee » srfi-14 » char-set-every

The char-set-every procedure returns true if predicate PRED returns true of every character in the character set CS. Likewise, char-set-any applies PRED to every character in character set CS, and returns the first true value it finds. If no character produces a true value, it returns false. The order in which these procedures sequence through the elements of CS is not specified.

Note that if you need to determine the actual character on which a predicate returns true, use char-set-any and arrange for the predicate to return the character parameter as its true value, e.g.

(char-set-any (lambda (c) (and (char-upper-case? c) c)) 
              cs)