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diff --git a/nixos/doc/manual/configuration/summary.section.md b/nixos/doc/manual/configuration/summary.section.md deleted file mode 100644 index 8abbbe257fd90..0000000000000 --- a/nixos/doc/manual/configuration/summary.section.md +++ /dev/null @@ -1,46 +0,0 @@ -# Syntax Summary {#sec-nix-syntax-summary} - -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 [Nix -manual](https://nixos.org/nix/manual/#chap-writing-nix-expressions) for -the rest. - -| Example | Description | -|-----------------------------------------------|--------------------------------------------------------------------------------------------------------------------| -| *Basic values* | | -| `"Hello world"` | A string | -| `"${pkgs.bash}/bin/sh"` | A string containing an expression (expands to `"/nix/store/hash-bash-version/bin/sh"`) | -| `true`, `false` | Booleans | -| `123` | An integer | -| `./foo.png` | A path (relative to the containing Nix expression) | -| *Compound values* | | -| `{ x = 1; y = 2; }` | A set with attributes named `x` and `y` | -| `{ foo.bar = 1; }` | A nested set, equivalent to `{ foo = { bar = 1; }; }` | -| `rec { x = "foo"; y = x + "bar"; }` | A recursive set, equivalent to `{ x = "foo"; y = "foobar"; }` | -| `[ "foo" "bar" ]` | A list with two elements | -| *Operators* | | -| `"foo" + "bar"` | String concatenation | -| `1 + 2` | Integer addition | -| `"foo" == "f" + "oo"` | Equality test (evaluates to `true`) | -| `"foo" != "bar"` | Inequality test (evaluates to `true`) | -| `!true` | Boolean negation | -| `{ x = 1; y = 2; }.x` | Attribute selection (evaluates to `1`) | -| `{ x = 1; y = 2; }.z or 3` | Attribute selection with default (evaluates to `3`) | -| `{ x = 1; y = 2; } // { z = 3; }` | Merge two sets (attributes in the right-hand set taking precedence) | -| *Control structures* | | -| `if 1 + 1 == 2 then "yes!" else "no!"` | Conditional expression | -| `assert 1 + 1 == 2; "yes!"` | Assertion check (evaluates to `"yes!"`). See [](#sec-assertions) for using assertions in modules | -| `let x = "foo"; y = "bar"; in x + y` | Variable definition | -| `with pkgs.lib; head [ 1 2 3 ]` | Add all attributes from the given set to the scope (evaluates to `1`) | -| *Functions (lambdas)* | | -| `x: x + 1` | A function that expects an integer and returns it increased by 1 | -| `(x: x + 1) 100` | A function call (evaluates to 101) | -| `let inc = x: x + 1; in inc (inc (inc 100))` | A function bound to a variable and subsequently called by name (evaluates to 103) | -| `{ x, y }: x + y` | A function that expects a set with required attributes `x` and `y` and concatenates them | -| `{ x, y ? "bar" }: x + y` | A function that expects a set with required attribute `x` and optional `y`, using `"bar"` as default value for `y` | -| `{ x, y, ... }: x + y` | A function that expects a set with required attributes `x` and `y` and ignores any other attributes | -| `{ x, y } @ args: x + y` | A function that expects a set with required attributes `x` and `y`, and binds the whole set to `args` | -| *Built-in functions* | | -| `import ./foo.nix` | Load and return Nix expression in given file | -| `map (x: x + x) [ 1 2 3 ]` | Apply a function to every element of a list (evaluates to `[ 2 4 6 ]`) | |