Im trying to write a simple scheme function that returns the last element of a list. My function looks like it should work, but I managed to fail on something: (define (last_element l)( (cond (nu...

For example: if I want the function equal? recognize my own type or record, can I add a new behavior of equal?? without erasing or overwriting the old one? Or for example if I want to make the fun...

I created this solution: ; use like this: ; (/* content ... */ <default-return>) ; or ; (/* content ... */) => #f (define-syntax /* (syntax-rules (*/) ((/* body ... */) #f) ((/* body ....

I can use SHA256 in Scheme using external libraries (Java, C or system dependent) or using a specific Scheme implementation (like Chicken e.g.), but I wonder if there is a "pure" scheme implementat...

Inspired by a comment thread on a related question regarding functions instead of macros. Is there any way to extend a Scheme syntax definition so that it can use the previous definition of the sy...

For example, I have this string: "6119726089.12814713" If I do (string->number "6119726089.12814713") - using the SISC implementation the result is 6.119726089128147e9 - and in Guile implementa...

In addition to question What's the explanation for Exercise 1.6 in SICP?. So Dr. Racket (R5RS) evaluates sqrt-iter function with "if" in finite time, clearly showing normal order evaluation. Bu...

I need a subroutine for my program written in scheme that takes an integer, say 34109, and puts it into a list with elements 3, 4, 1, 0, 9. The integer can be any length. Does anyone have a trick f...

I've got a bunch of "legacy" Guile Scheme code that I want to get running in the Racket Scheme IDE. There appear to be enough differences to make this a non-trivial exercise. (My level of Scheme kn...

This is concerning chapter 3.5 from SICP, in which streams are being discussed. The idea is that: (cons-stream 1 (display 'hey)) Should not evaluate the second part of the cons-stream, so it sho...

I'm relatively new to scheme and am having a hard time finding a concrete document online overviewing the major changes that happened with R6RS. Anyone care to elaborate?