sass-site/source/documentation/at-rules/control/each.html.md.erb
2018-10-23 13:42:40 -07:00

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---
title: "@each"
---
The `@each` rule makes it easy to emit styles or evaluate code for each element
of a [list][] or each pair in a [map][]. It's great for repetitive styles that
only have a few variations between them. It's usually written
`@each <variable> in <expression> { ... }`, where the [expression][] returns a
list. The block is evaluated for each element of the list in turn, which is
assigned to the given variable name.
[list]: ../values/lists
[map]: ../values/maps
[expression]: ../syntax/structure#expressions
<%= partial 'code-snippets/example-each-list' %>
## With Maps
You can also use `@each` to iterate over every key/value pair in a map by
writing it `@each <variable>, <variable> in <expression> { ... }`. The key is
assigned to the first variable name, and the element is assigned to the second.
<%= partial 'code-snippets/example-each-map' %>
## Destructuring
If you have a list of lists, you can use `@each` to automatically assign
variables to each of the values from the inner lists by writing it
`@each <variable...> in <expression> { ... }`. This is known as *destructuring*,
since the variables match the structure of the inner lists. Each variable name
is assigned to the value at the corresponding position in the list, or
[`null`][] if the list doesn't have enough values.
[`null`]: ../../values/null
<% example do %>
$icons:
"eye" "\f112" 12px,
"start" "\f12e" 16px,
"stop" "\f12f" 10px;
@each $name, $glyph, $size in $icons {
.icon-#{$name}:before {
display: inline-block;
font-family: "Icon Font";
content: $glyph;
font-size: $size;
}
}
===
$icons: "eye" "\f112" 12px, "start" "\f12e" 16px, "stop" "\f12f" 10px;
@each $name, $glyph, $size in $icons
.icon-#{$name}:before
display: inline-block
font-family: "Icon Font"
content: $glyph
font-size: $size
<% end %>
<% fun_fact do %>
Because `@each` supports destructuring and [maps count as lists of lists][],
`@each`'s map support works without needing special support for maps in
particular.
[maps count as lists of lists]: ../../values/maps
<% end %>