A bunch of versions of Scheme are missing things like range and map (a good example is LispMe lacks both, chicken lacks range). This repo contains an oklib.scm file with bad (performance) but working equivalents, prepended with ok (so they don't get in the way of the built-ins your version of scheme has).

I test this with Gambit, Guile, Racket and Chicken (and sometimes LispMe).

To use this functions just load the scheme file e.g.:

> (load "oklib.scm")
"/home/uccaoke/Source/okschemelib/oklib.scm"
> (okmap (lambda (x) (+ x 1)) (okrange 0.5 10 1))  
(1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5 9.5 10.5)
> 

For novelty's sake I've also been implementing the same routines in Common LISP. You can find them in oklib.cl. You don't need okmap really because map is a core part of Common LISP, but it was an interesting exercise to implement it!

[1]> (load "oklib.cl")
;; Loading file oklib.cl ...
;; Loaded file oklib.cl
T
[2]> (okmap #'(lambda (x) (+ x 1)) (okrange 0.5 10 1))
(1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5 9.5 10.5)
[3]> 

There is now a third version, for xlisp 2.1 on Macintosh in OKLIB.LSP, containing functions missing from xlisp, specifically range.

All implentations include some functions for checking to see if a string ends with or starts with another string (varies by implementation).