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doc: cookbook: Mention common SRFI-1 procedures.

* doc/guix-cookbook.texi (A Scheme Crash Course): Add item about
SRFI-1.
Ludovic Courtès 2023-08-14 15:08:00 +02:00
parent 3c7d465133
commit d20a7da4a3
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1 changed files with 29 additions and 1 deletions

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@ -192,7 +192,8 @@ rest are the arguments passed to the function. Every function returns the
last evaluated expression as its return value.
@item
Anonymous functions are declared with the @code{lambda} term:
Anonymous functions---@dfn{procedures} in Scheme parlance---are declared
with the @code{lambda} term:
@lisp
(lambda (x) (* x x))
@ -208,6 +209,9 @@ which can in turn be applied to an argument:
@result{} 9
@end lisp
Procedures are regular values just like numbers, strings, Booleans, and
so on.
@item
Anything can be assigned a global name with @code{define}:
@ -233,6 +237,30 @@ A list structure can be created with the @code{list} procedure:
@result{} (2 3 5 7)
@end lisp
@item
Standard procedures are provided by the @code{(srfi srfi-1)} module to
create and process lists (@pxref{SRFI-1, list processing,, guile, GNU
Guile Reference Manual}). Here are some of the most useful ones in
action:
@lisp
(use-modules (srfi srfi-1)) ;import list processing procedures
(append (list 1 2) (list 3 4))
@result{} (1 2 3 4)
(map (lambda (x) (* x x)) (list 1 2 3 4))
@result{} (1 4 9 16)
(delete 3 (list 1 2 3 4)) @result{} (1 2 4)
(filter odd? (list 1 2 3 4)) @result{} (1 3)
(remove even? (list 1 2 3 4)) @result{} (1 3)
(find number? (list "a" 42 "b")) @result{} 42
@end lisp
Notice how the first argument to @code{map}, @code{filter},
@code{remove}, and @code{find} is a procedure!
@item
@cindex S-expression
The @dfn{quote} disables evaluation of a parenthesized expression, also