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Diffstat (limited to 'nixos/doc/manual/configuration/summary.xml')
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diff --git a/nixos/doc/manual/configuration/summary.xml b/nixos/doc/manual/configuration/summary.xml deleted file mode 100644 index 289face16de..00000000000 --- a/nixos/doc/manual/configuration/summary.xml +++ /dev/null @@ -1,227 +0,0 @@ -<section xmlns="http://docbook.org/ns/docbook" - xmlns:xlink="http://www.w3.org/1999/xlink" - xmlns:xi="http://www.w3.org/2001/XInclude" - version="5.0" - xml:id="sec-nix-syntax-summary"> - <title>Syntax Summary</title> - - <para> - Below is a summary of the most important syntactic constructs in the Nix - expression language. It’s not complete. In particular, there are many other - built-in functions. See the - <link -xlink:href="https://nixos.org/nix/manual/#chap-writing-nix-expressions">Nix - manual</link> for the rest. - </para> - - <informaltable frame='none'> - <tgroup cols='2'> - <colspec colname='c1' rowsep='1' colsep='1' /> - <colspec colname='c2' rowsep='1' /> - <thead> - <row> - <entry>Example</entry> - <entry>Description</entry> - </row> - </thead> - <tbody> - <row> - <entry namest="c1" nameend="c2"><emphasis>Basic values</emphasis> - </entry> - </row> - <row> - <entry><literal>"Hello world"</literal> - </entry> - <entry>A string</entry> - </row> - <row> - <entry><literal>"${pkgs.bash}/bin/sh"</literal> - </entry> - <entry>A string containing an expression (expands to <literal>"/nix/store/<replaceable>hash</replaceable>-bash-<replaceable>version</replaceable>/bin/sh"</literal>)</entry> - </row> - <row> - <entry><literal>true</literal>, <literal>false</literal> - </entry> - <entry>Booleans</entry> - </row> - <row> - <entry><literal>123</literal> - </entry> - <entry>An integer</entry> - </row> - <row> - <entry><literal>./foo.png</literal> - </entry> - <entry>A path (relative to the containing Nix expression)</entry> - </row> - <row> - <entry namest="c1" nameend="c2"><emphasis>Compound values</emphasis> - </entry> - </row> - <row> - <entry><literal>{ x = 1; y = 2; }</literal> - </entry> - <entry>A set with attributes named <literal>x</literal> and <literal>y</literal> - </entry> - </row> - <row> - <entry><literal>{ foo.bar = 1; }</literal> - </entry> - <entry>A nested set, equivalent to <literal>{ foo = { bar = 1; }; }</literal> - </entry> - </row> - <row> - <entry><literal>rec { x = "foo"; y = x + "bar"; }</literal> - </entry> - <entry>A recursive set, equivalent to <literal>{ x = "foo"; y = "foobar"; }</literal> - </entry> - </row> - <row> - <entry><literal>[ "foo" "bar" ]</literal> - </entry> - <entry>A list with two elements</entry> - </row> - <row> - <entry namest="c1" nameend="c2"><emphasis>Operators</emphasis> - </entry> - </row> - <row> - <entry><literal>"foo" + "bar"</literal> - </entry> - <entry>String concatenation</entry> - </row> - <row> - <entry><literal>1 + 2</literal> - </entry> - <entry>Integer addition</entry> - </row> - <row> - <entry><literal>"foo" == "f" + "oo"</literal> - </entry> - <entry>Equality test (evaluates to <literal>true</literal>)</entry> - </row> - <row> - <entry><literal>"foo" != "bar"</literal> - </entry> - <entry>Inequality test (evaluates to <literal>true</literal>)</entry> - </row> - <row> - <entry><literal>!true</literal> - </entry> - <entry>Boolean negation</entry> - </row> - <row> - <entry><literal>{ x = 1; y = 2; }.x</literal> - </entry> - <entry>Attribute selection (evaluates to <literal>1</literal>)</entry> - </row> - <row> - <entry><literal>{ x = 1; y = 2; }.z or 3</literal> - </entry> - <entry>Attribute selection with default (evaluates to <literal>3</literal>)</entry> - </row> - <row> - <entry><literal>{ x = 1; y = 2; } // { z = 3; }</literal> - </entry> - <entry>Merge two sets (attributes in the right-hand set taking precedence)</entry> - </row> - <row> - <entry namest="c1" nameend="c2"><emphasis>Control structures</emphasis> - </entry> - </row> - <row> - <entry><literal>if 1 + 1 == 2 then "yes!" else "no!"</literal> - </entry> - <entry>Conditional expression</entry> - </row> - <row> - <entry><literal>assert 1 + 1 == 2; "yes!"</literal> - </entry> - <entry>Assertion check (evaluates to <literal>"yes!"</literal>). See <xref - linkend="sec-assertions"/> for using assertions in modules</entry> - </row> - <row> - <entry><literal>let x = "foo"; y = "bar"; in x + y</literal> - </entry> - <entry>Variable definition</entry> - </row> - <row> - <entry><literal>with pkgs.lib; head [ 1 2 3 ]</literal> - </entry> - <entry>Add all attributes from the given set to the scope - (evaluates to <literal>1</literal>)</entry> - </row> - <row> - <entry namest="c1" nameend="c2"><emphasis>Functions (lambdas)</emphasis> - </entry> - </row> - <row> - <entry><literal>x: x + 1</literal> - </entry> - <entry>A function that expects an integer and returns it increased by 1</entry> - </row> - <row> - <entry><literal>(x: x + 1) 100</literal> - </entry> - <entry>A function call (evaluates to 101)</entry> - </row> - <row> - <entry><literal>let inc = x: x + 1; in inc (inc (inc 100))</literal> - </entry> - <entry>A function bound to a variable and subsequently called by name (evaluates to 103)</entry> - </row> - <row> - <entry><literal>{ x, y }: x + y</literal> - </entry> - <entry>A function that expects a set with required attributes - <literal>x</literal> and <literal>y</literal> and concatenates - them</entry> - </row> - <row> - <entry><literal>{ x, y ? "bar" }: x + y</literal> - </entry> - <entry>A function that expects a set with required attribute - <literal>x</literal> and optional <literal>y</literal>, using - <literal>"bar"</literal> as default value for - <literal>y</literal> - </entry> - </row> - <row> - <entry><literal>{ x, y, ... }: x + y</literal> - </entry> - <entry>A function that expects a set with required attributes - <literal>x</literal> and <literal>y</literal> and ignores any - other attributes</entry> - </row> - <row> - <entry><literal>{ x, y } @ args: x + y</literal> - </entry> - <entry>A function that expects a set with required attributes - <literal>x</literal> and <literal>y</literal>, and binds the - whole set to <literal>args</literal> - </entry> - </row> - <row> - <entry namest="c1" nameend="c2"><emphasis>Built-in functions</emphasis> - </entry> - </row> - <row> - <entry><literal>import ./foo.nix</literal> - </entry> - <entry>Load and return Nix expression in given file</entry> - </row> - <row> - <entry><literal>map (x: x + x) [ 1 2 3 ]</literal> - </entry> - <entry>Apply a function to every element of a list (evaluates to <literal>[ 2 4 6 ]</literal>)</entry> - </row> -<!-- - <row> - <entry><literal>throw "Urgh"</literal></entry> - <entry>Raise an error condition</entry> - </row> - --> - </tbody> - </tgroup> - </informaltable> -</section> |