重大变化：斜线作为除法

Sass 目前在某些上下文中将 / 视为除法运算，在其他上下文中将 / 视为分隔符。这使得 Sass 用户很难判断任何给定的 / 的含义，并且很难使用使用 / 作为分隔符的新 CSS 功能。

Dart Sass: partial
LibSass: ✗
Ruby Sass: ✗

今天，Sass 使用复杂的启发法来确定 / 是否应该被视为除法或分隔符。即使这样，作为分隔符，它也只会生成一个不带引号的字符串，很难从 Sass 内部检查。随着越来越多的 CSS 功能（例如 CSS 网格和新的 rgb() 和 hsl() 语法）使用 / 作为分隔符，这对于 Sass 用户来说变得越来越痛苦。

¥Today, Sass uses complex heuristics to figure out whether a / should be treated as division or a separator. Even then, as a separator it just produces an unquoted string that’s difficult to inspect from within Sass. As more and more CSS features like CSS Grid and the new rgb() and hsl() syntax use / as a separator, this is becoming more and more painful to Sass users.

因为 Sass 是 CSS 超集，所以我们通过将 / 重新定义为仅分隔符来匹配 CSS 语法。/ 将被视为一种新型列表分隔符，类似于当今 , 的工作方式。除法将改为使用新的 math.div() 函数编写。该函数的行为与 / 今天的行为完全相同。

¥Because Sass is a CSS superset, we’re matching CSS’s syntax by redefining / to be only a separator. / will be treated as a new type of list separator, similar to how , works today. Division will instead be written using the new math.div() function. This function will behave exactly the same as / does today.

此弃用不会影响 / 在 calc() 表达式中的使用。

¥This deprecation does not affect uses of / inside calc() expressions.

  SCSS

  Sass

  CSS

      
      Playground
    SCSS Syntax@use "sass:math";

// Future Sass, doesn't work yet!
.item3 {
  $row: span math.div(6, 2) / 7; // A two-element slash-separated list.
  grid-row: $row;
}

      
      Playground
    Sass Syntax@use "sass:math"

// Future Sass, doesn't work yet!
.item3
  $row: span math.div(6, 2) / 7 // A two-element slash-separated list.
  grid-row: $row

CSS Output.item3 {
  grid-row: span 3 / 7;
}

过渡期过渡期 permalink

¥Transition Period

Dart Sass: since 1.33.0
LibSass: ✗
Ruby Sass: ✗

为了简化过渡，我们首先添加 math.div() 函数。/ 运算符目前仍然执行除法，但执行此操作时还会打印一条弃用警告。用户应将所有分区切换为使用 math.div()。

¥To ease the transition, we’ve begun by adding the math.div() function. The / operator still does division for now, but it also prints a deprecation warning when it does so. Users should switch all division to use math.div() instead.

💡 Fun fact:

Remember, you can silence deprecation warnings from libraries you don’t control! If you’re using the command-line interface you can pass the --quiet-deps flag, and if you’re using the JavaScript API you can set the quietDeps option to true.

  SCSS

  Sass

      
      Playground
    SCSS Syntax@use "sass:math";

// WRONG, will not work in future Sass versions.
@debug (12px/4px); // 3

// RIGHT, will work in future Sass versions.
@debug math.div(12px, 4px); // 3

      
      Playground
    Sass Syntax@use "sass:math"

// WRONG, will not work in future Sass versions.
@debug (12px/4px) // 3

// RIGHT, will work in future Sass versions.
@debug math.div(12px, 4px) // 3

过渡期间也将提供斜杠分隔的列表。由于还无法使用 / 创建它们，因此将添加 list.slash() 函数来创建它们。你还可以将 "slash" 作为 $separator 传递给 list.join() 函数和 list.append() 函数。

¥Slash-separated lists will also be available in the transition period. Because they can’t be created with / yet, the list.slash() function will be added to create them. You will also be able to pass "slash" as the $separator to the list.join() function and the list.append() function.

  SCSS

  Sass

  CSS

      
      Playground
    SCSS Syntax@use "sass:list";
@use "sass:math";

.item3 {
  $row: list.slash(span math.div(6, 2), 7);
  grid-row: $row;
}

      
      Playground
    Sass Syntax@use "sass:list"
@use "sass:math"

.item3
  $row: list.slash(span math.div(6, 2), 7)
  grid-row: $row

CSS Output.item3 {
  grid-row: span 3 / 7;
}

Dart Sass: since 1.40.0
LibSass: ✗
Ruby Sass: ✗

或者，用户可以将除法运算封装在 calc() 表达式中，Sass 会将其简化为单个数字。

¥Alternatively, users can wrap division operations inside a calc() expression, which Sass will simplify to a single number.

  SCSS

  Sass

      
      Playground
    SCSS Syntax// WRONG, will not work in future Sass versions.
@debug (12px/4px); // 3

// RIGHT, will work in future Sass versions.
@debug calc(12px / 4px); // 3

      
      Playground
    Sass Syntax// WRONG, will not work in future Sass versions.
@debug (12px/4px) // 3

// RIGHT, will work in future Sass versions.
@debug calc(12px / 4px) // 3

自动迁移自动迁移 permalink

¥Automatic Migration

你可以使用 Sass 迁移器自动更新样式表以使用 math.div() 和 list.slash()。

¥You can use the Sass migrator to automatically update your stylesheets to use math.div() and list.slash().

$ npm install -g sass-migrator
$ sass-migrator division **/*.scss

Can I Silence the Warnings?Can I Silence the Warnings? permalink

Sass provides a powerful suite of options for managing which deprecation warnings you see and when.

Terse and Verbose ModeTerse and Verbose Mode permalink

By default, Sass runs in terse mode, where it will only print each type of deprecation warning five times before it silences additional warnings. This helps ensure that users know when they need to be aware of an upcoming breaking change without creating an overwhelming amount of console noise.

If you run Sass in verbose mode instead, it will print every deprecation warning it encounters. This can be useful for tracking the remaining work to be done when fixing deprecations. You can enable verbose mode using the --verbose flag on the command line, or the verbose option in the JavaScript API.

⚠️ Heads up!

When running from the JS API, Sass doesn’t share any information across compilations, so by default it’ll print five warnings for each stylesheet that’s compiled. However, you can fix this by writing (or asking the author of your favorite framework’s Sass plugin to write) a custom Logger that only prints five errors per deprecation and can be shared across multiple compilations.

Silencing Deprecations in DependenciesSilencing Deprecations in Dependencies permalink

Sometimes, your dependencies have deprecation warnings that you can’t do anything about. You can silence deprecation warnings from dependencies while still printing them for your app using the --quiet-deps flag on the command line, or the quietDeps option in the JavaScript API.

For the purposes of this flag, a "dependency" is any stylesheet that’s not just a series of relative loads from the entrypoint stylesheet. This means anything that comes from a load path, and most stylesheets loaded through custom importers.

Silencing Specific DeprecationsSilencing Specific Deprecations permalink

If you know that one particular deprecation isn’t a problem for you, you can silence warnings for that specific deprecation using the --silence-deprecation flag on the command line, or the silenceDeprecations option in the JavaScript API.