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Diffstat (limited to 'doc/guix-cookbook.texi')
| -rw-r--r-- | doc/guix-cookbook.texi | 86 |
1 files changed, 43 insertions, 43 deletions
diff --git a/doc/guix-cookbook.texi b/doc/guix-cookbook.texi index 3fee6b270e..1b081a820e 100644 --- a/doc/guix-cookbook.texi +++ b/doc/guix-cookbook.texi @@ -125,14 +125,14 @@ and @code{#f} stand for the booleans "true" and "false", respectively. Examples of valid expressions: -@example scheme +@lisp > "Hello World!" "Hello World!" > 17 17 > (display (string-append "Hello " "Guix" "\n")) "Hello Guix!" -@end example +@end lisp @item This last example is a function call nested in another function call. When a @@ -143,66 +143,66 @@ last evaluated expression as its return value. @item Anonymous functions are declared with the @code{lambda} term: -@example scheme +@lisp > (lambda (x) (* x x)) #<procedure 120e348 at <unknown port>:24:0 (x)> -@end example +@end lisp The above procedure returns the square of its argument. Since everything is an expression, the @code{lambda} expression returns an anonymous procedure, which can in turn be applied to an argument: -@example scheme +@lisp > ((lambda (x) (* x x)) 3) 9 -@end example +@end lisp @item Anything can be assigned a global name with @code{define}: -@example scheme +@lisp > (define a 3) > (define square (lambda (x) (* x x))) > (square a) 9 -@end example +@end lisp @item Procedures can be defined more concisely with the following syntax: -@example scheme +@lisp (define (square x) (* x x)) -@end example +@end lisp @item A list structure can be created with the @code{list} procedure: -@example scheme +@lisp > (list 2 a 5 7) (2 3 5 7) -@end example +@end lisp @item The @emph{quote} disables evaluation of a parenthesized expression: the first term is not called over the other terms. Thus it effectively returns a list of terms. -@example scheme +@lisp > '(display (string-append "Hello " "Guix" "\n")) (display (string-append "Hello " "Guix" "\n")) > '(2 a 5 7) (2 a 5 7) -@end example +@end lisp @item The @emph{quasiquote} disables evaluation of a parenthesized expression until a comma re-enables it. Thus it provides us with fine-grained control over what is evaluated and what is not. -@example scheme +@lisp > `(2 a 5 7 (2 ,a 5 ,(+ a 4))) (2 a 5 7 (2 3 5 7)) -@end example +@end lisp Note that the above result is a list of mixed elements: numbers, symbols (here @code{a}) and the last element is a list itself. @@ -210,7 +210,7 @@ Note that the above result is a list of mixed elements: numbers, symbols (here @item Multiple variables can be named locally with @code{let}: -@example scheme +@lisp > (define x 10) > (let ((x 2) (y 3)) @@ -220,17 +220,17 @@ Multiple variables can be named locally with @code{let}: 10 > y ERROR: In procedure module-lookup: Unbound variable: y -@end example +@end lisp Use @code{let*} to allow later variable declarations to refer to earlier definitions. -@example scheme +@lisp > (let* ((x 2) (y (* x 3))) (list x y)) (2 6) -@end example +@end lisp @item The keyword syntax is @code{#:}; it is used to create unique identifiers. @@ -244,12 +244,12 @@ Scheme treats @code{%} exactly the same as any other letter. @item Modules are created with @code{define-module}. For instance -@example scheme +@lisp (define-module (guix build-system ruby) #:use-module (guix store) #:export (ruby-build ruby-build-system)) -@end example +@end lisp defines the module @code{guix build-system ruby} which must be located in @file{guix/build-system/ruby.scm} somewhere in the Guile load path. It @@ -343,7 +343,7 @@ install}). Guix already provides a package definition which is a perfect example to start with. You can look up its declaration with @code{guix edit hello} from the command line. Let's see how it looks: -@example scheme +@lisp (define-public hello (package (name "hello") @@ -363,7 +363,7 @@ serves as an example of standard GNU coding practices. As such, it supports command-line arguments, multiple languages, and so on.") (home-page "https://www.gnu.org/software/hello/") (license gpl3+))) -@end example +@end lisp As you can see, most of it is rather straightforward. But let's review the fields together: @@ -423,7 +423,7 @@ setup later; for now we will go the simplest route. Save the following to a file @file{my-hello.scm}. -@example scheme +@lisp (use-modules (guix packages) (guix download) (guix build-system gnu) @@ -447,7 +447,7 @@ serves as an example of standard GNU coding practices. As such, it supports command-line arguments, multiple languages, and so on.") (home-page "https://www.gnu.org/software/hello/") (license gpl3+)) -@end example +@end lisp We will explain the extra code in a moment. @@ -564,7 +564,7 @@ nature of how the package definition is written. The @code{linux-libre} kernel package definition is actually a procedure which creates a package. -@example scheme +@lisp (define* (make-linux-libre version hash supported-systems #:key ;; A function that takes an arch and a variant. @@ -575,19 +575,19 @@ creates a package. (extra-options %default-extra-linux-options) (patches (list %boot-logo-patch))) ...) -@end example +@end lisp The current @code{linux-libre} package is for the 5.1.x series, and is declared like this: -@example scheme +@lisp (define-public linux-libre (make-linux-libre %linux-libre-version %linux-libre-hash '("x86_64-linux" "i686-linux" "armhf-linux" "aarch64-linux") #:patches %linux-libre-5.1-patches #:configuration-file kernel-config)) -@end example +@end lisp Any keys which are not assigned values inherit their default value from the @code{make-linux-libre} definition. When comparing the two snippets above, @@ -603,7 +603,7 @@ including an actual @file{.config} file as a native input to our custom kernel. The following is a snippet from the custom @code{'configure} phase of the @code{make-linux-libre} package definition: -@example scheme +@lisp (let ((build (assoc-ref %standard-phases 'build)) (config (assoc-ref (or native-inputs inputs) "kconfig"))) @@ -614,13 +614,13 @@ the @code{make-linux-libre} package definition: (copy-file config ".config") (chmod ".config" #o666)) (invoke "make" ,defconfig)) -@end example +@end lisp Below is a sample kernel package. The @code{linux-libre} package is nothing special and can be inherited from and have its fields overridden like any other package: -@example scheme +@lisp (define-public linux-libre/E2140 (package (inherit linux-libre) @@ -628,7 +628,7 @@ other package: `(("kconfig" ,(local-file "E2140.config")) ,@@(alist-delete "kconfig" (package-native-inputs linux-libre)))))) -@end example +@end lisp In the same directory as the file defining @code{linux-libre-E2140} is a file named @file{E2140.config}, which is an actual kernel configuration file. The @@ -641,7 +641,7 @@ The second way to create a custom kernel is to pass a new value to the @code{extra-options} keyword works with another function defined right below it: -@example scheme +@lisp (define %default-extra-linux-options `(;; https://lists.gnu.org/archive/html/guix-devel/2014-04/msg00039.html ("CONFIG_DEVPTS_MULTIPLE_INSTANCES" . #t) @@ -667,11 +667,11 @@ it: (string-append option "=n"))) options) "\n")) -@end example +@end lisp And in the custom configure script from the `make-linux-libre` package: -@example scheme +@lisp ;; Appending works even when the option wasn't in the ;; file. The last one prevails if duplicated. (let ((port (open-file ".config" "a")) @@ -680,13 +680,13 @@ And in the custom configure script from the `make-linux-libre` package: (close-port port)) (invoke "make" "oldconfig")))) -@end example +@end lisp So by not providing a configuration-file the @file{.config} starts blank, and then we write into it the collection of flags that we want. Here's another custom kernel: -@example scheme +@lisp (define %macbook41-full-config (append %macbook41-config-options %filesystems @@ -703,7 +703,7 @@ custom kernel: #:extra-version "macbook41" #:patches (@@@@ (gnu packages linux) %linux-libre-5.1-patches) #:extra-options %macbook41-config-options)) -@end example +@end lisp In the above example @code{%filesystems} is a collection of flags enabling different filesystem support, @code{%efi-support} enables EFI support and @@ -876,7 +876,7 @@ Let's dive in the set up! A Guix profile can be set up @emph{via} a so-called @emph{manifest specification} that looks like this: -@example +@lisp (specifications->manifest '("package-1" ;; Version 1.3 of package-2. @@ -885,9 +885,9 @@ this: "package-3:lib" ; ... "package-N")) -@end example +@end lisp -See @pxref{Invoking guix package,,, guix, GNU Guix Reference Manual} for +@pxref{Invoking guix package,,, guix, GNU Guix Reference Manual}, for the syntax details. We can create a manifest specification per profile and install them this way: |