--- title: "@forward" introduction: > The `@forward` rule loads a Sass stylesheet and makes its [mixins](mixin), [functions](function), and [variables](../variables) available when your stylesheet is loaded with the [`@use` rule](use). It makes it possible to organize Sass libraries across many files, while allowing their users to load a single entrypoint file. --- The rule is written `@forward ""`. It loads the module at the given URL just like `@use`, but it makes the [public][] members of the loaded module available to users of your module as though they were defined directly in your module. Those members aren't available in your module, though—if you want that, you'll need to write a `@use` rule as well. Don't worry, it'll only load the module once! [public]: use#private-members If you *do* write both a `@forward` and a `@use` for the same module in the same file, it's always a good idea to write the `@forward` first. That way, if your users want to [configure the forwarded module][], that configuration will be applied to the `@forward` before your `@use` loads it without any configuration. [configure the forwarded module]: use#configuration <% fun_fact do %> The `@forward` rule acts just like `@use` when it comes to a module's CSS. Styles from a forwarded module will be included in the compiled CSS output, and the module with the `@forward` can [extend][] it, even if it isn't also `@use`d. [extend]: extend <% end %> <% example do %> // src/_list.scss @mixin list-reset { margin: 0; padding: 0; list-style: none; } --- // bootstrap.scss @forward "src/list"; --- // styles.scss @use "bootstrap"; li { @include bootstrap.list-reset; } === // src/_list.sass @mixin list-reset margin: 0 padding: 0 list-style: none --- // bootstrap.sass @forward "src/list" --- // styles.sass @use "bootstrap" li @include bootstrap.list-reset === li { margin: 0; padding: 0; list-style: none; } <% end %> ## Adding a Prefix Because module members are usually used with [a namespace][], short and simple names are usually the most readable option. But those names might not make sense outside the module they're defined in, so `@forward` has the option of adding an extra prefix to all the members it forwards. This is written `@forward "" as -*`, and it adds the given prefix to the beginning of every mixin, function, and variable name forwarded by the module. For example, if the module defines a member named `reset` and it's forwarded `as list-*`, downstream stylesheets will refer to it as `list-reset`. [a namespace]: use#loading-members <% example do %> // src/_list.scss @mixin reset { margin: 0; padding: 0; list-style: none; } --- // bootstrap.scss @forward "src/list" as list-*; --- // styles.scss @use "bootstrap"; li { @include bootstrap.list-reset; } === // src/_list.sass @mixin reset margin: 0 padding: 0 list-style: none --- // bootstrap.sass @forward "src/list" as list-* --- // styles.sass @use "bootstrap" li @include bootstrap.list-reset === li { margin: 0; padding: 0; list-style: none; } <% end %> ## Controlling Visibility Sometimes, you don't want to forward *every* member from a module. You may want to keep some members private so that only your package can use them, or you may want to require your users to load some members a different way. You can control exactly which members get forwarded by writing `@forward "" hide ` or `@forward "" show `. The `hide` form means that the listed members shouldn't be forwarded, but everything else should. The `show` form means that *only* the named members should be forwarded. In both forms, you list the names of mixins, functions, or variables (including the `$`). <% example(autogen_css: false) do %> // src/_list.scss $horizontal-list-gap: 2em; @mixin list-reset { margin: 0; padding: 0; list-style: none; } @mixin list-horizontal { @include reset; li { display: inline-block; margin: { left: -2px; right: $horizontal-list-gap; } } } --- // bootstrap.scss @forward "src/list" hide list-reset, $horizontal-list-gap; === // src/_list.sass $horizontal-list-gap: 2em @mixin list-reset margin: 0 padding: 0 list-style: none @mixin list-horizontal @include reset li display: inline-block margin: left: -2px right: $horizontal-list-gap --- // bootstrap.sass @forward "src/list" hide list-reset, $horizontal-list-gap <% end %> ## Configuring Modules <% impl_status dart: '1.24.0', libsass: false, ruby: false %> The `@forward` rule can also load a module with [configuration][]. This mostly works the same as it does for `@use`, with one addition: a `@forward` rule's configuration can use the `!default` flag in its configuration. This allows a module to change the defaults of an upstream stylesheet while still allowing downstream stylesheets to override them. [configuration]: use#configuration <% example do %> // _library.scss $black: #000 !default; $border-radius: 0.25rem !default; $box-shadow: 0 0.5rem 1rem rgba($black, 0.15) !default; code { border-radius: $border-radius; box-shadow: $box-shadow; } --- // _opinionated.scss @forward 'library' with ( $black: #222 !default, $border-radius: 0.1rem !default ); --- // style.scss @use 'opinionated' with ($black: #333); === // _library.sass $black: #000 !default $border-radius: 0.25rem !default $box-shadow: 0 0.5rem 1rem rgba($black, 0.15) !default code border-radius: $border-radius box-shadow: $box-shadow --- // _opinionated.sass @forward 'library' with ($black: #222 !default, $border-radius: 0.1rem !default) --- // style.sass @use 'opinionated' with ($black: #333) === code { border-radius: 0.1rem; box-shadow: 0 0.5rem 1rem rgba(51, 51, 51, 0.15); } <% end %>