Scheme

Vietnamese tutorial

• Introduction: https://pp.pymi.vn/article/scm1/
• Package management: https://pp.pymi.vn/article/scm_egg/

Documents

• For Python programmers: http://wiki.call-cc.org/chicken-for-python-programmers
• CHICKEN Scheme homepage http://eggs.call-cc.org/
• Teach you Scheme in fixed days http://ds26gte.github.io/tyscheme/
• HTDP https://htdp.org/2003-09-26/Book/curriculum-Z-H-1.html#node_toc_start

csi tips

csi command is interactive shell like python or ipython, some tips:

• Show help for a procedure/unit (function/module)

(use chicken-doc)
,doc KEYWORD

e.g ,doc fold

List

Creating

• '(a b c) ; List of symbol a b c
• '(1 2 a b) ; List of symbol 1 2 a b - 1 2 also is number
• (list 1 2 'a 'b) ; Same as above
• (iota 10) ; creates list 0->9
• (iota 5 1 2) ; creates list '(1 3 5 7 9) ; count=5 start=1 step=2
• (for-each print (iota 10)) ; print 0->9
• (make-list 10 1) ; (1 1 1 1 1 1 1 1 1 1)

Modifying

Add element to head of list

• (cons 1 '(a b c 2)) => (1 a b c 2) : CONStructing new list with 1 and the second list's elements
• (append '(a b c) '(2 3 4)) => (a b c 2 3 4) : create new list by concat two lists.

Transforming

(fold + 1 '(1 2 3)) ; => 7
(reduce + 1 '(1 2 3)) ; => 6 ; 1 only set when list empty

String processing

There are not much string process function.

String procedures provided by unit srfi-13

(use srfi-13)
(string-upcase "apymi")
OUTPUT: "APYMI"

Could also use many procedures in unit irregex

(use irregex)
(irregex-split " " " a b c hihi")
Output: ("a" "b" "c" "hihi")

Input/Ouput

Read all strings from a file:

(use utils)
(read-all "/etc/passwd")

Extension

Essential extensions:

• Unit library Basic Scheme definitions
• Unit eval Evaluation
• Unit expand Modules and macros handling
• Unit data-structures Data structures
• Unit ports I/O ports
• Unit files File and pathname operations
• Unit extras Useful utility definitions
• Unit irregex Regular expressions
• Unit srfi-1 List Library
• Unit srfi-4 Homogeneous numeric vectors
• Unit srfi-13 String library
• Unit srfi-14 Character set library
• Unit srfi-18 multithreading
• Unit srfi-69 Hashtable Library
• Unit posix Unix-like services
• Unit utils Shell scripting and file operations
• Unit tcp Basic TCP-sockets
• Unit lolevel Low-level operations

To use, just type (use srfi-1) for using unit srfi-1