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Scheme Cookbook

License

The code in the cookbook is released under several common licenses simultaneously. The user is free to pick any one of them. The aim is to make it easy to copy code into existing projects without having to add a new license notice to cover the cookbook material.

The licenses are: CC0-1.0, ISC, MIT, BSD-3-Clause, LGPL-2.1-or-later

Recipes

Pairs and lists

• Check if all elements are equal
• Create K combinations from list
• Find depth of list
• Find index of element in list
• Find most frequent element in list
• Find stride across lists
• Fold over n consecutive elements inside a list
• Index a list
• Map over n consecutive elements inside a list
• Remove duplicates from list
• Remove element from list
• Select first n elements from a list
• Select random elements from list
• Split list into groups by comparator
• Split list into groups of N elements
• Split list into groups that are equal judging by a procedure
• Test if all items in list pass the predicate
• Test if list is ordered by comparator

Association lists, property lists, and hash tables

• Filter alist keys

Data structures

• Use list as queue
• Use list as set
• Use list as stack
• Use lists as 2D matrix

Algorithms

• Nondeterminism using amb
• Topological sort

Strings

• Convert any value to string
• Find substring in string
• Join list of strings with delimiter
• Remove whitespace from string
• Split string

Numbers

• Compute Pascal's triangle
• Convert integer to list of digits
• Convert list of digits into integer

Time

• Format Unix timestamp

File system

• Find matching files in directory tree

Reflection

• Get type of object

Macros

• Bind optional arguments
• Check for symbol in syntax-rules
• Define symbols
• Unicode lambda

Tool integrations

• Display Unicode symbols in Emacs

About cookbook.scheme.org

cookbook.scheme.org is a community subdomain of scheme.org

• Source code: schemedoc/cookbook repository on GitHub.
• Discussion: schemeorg mailing list (archives, subscribe).

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