Sass Introspection Functions
Sass Introspection functions are rarely used for building stylesheets; they are generally used for debugging code.
The following table lists Sass's Introspection functions:
| Function | Description & Example |
|---|---|
| call(function, arguments...) | Dynamic call of a function, i.e., calling the function with arguments as parameters and returning the result. |
| content-exists() | Check whether the current mixin is passed a @content block. |
| feature-exists(feature) | Check whether the current Sass implementation supports the feature. Example: feature-exists("at-error"); Result: true |
| function-exists(functionname) | Detect whether the specified function exists Example: function-exists("nonsense") Result: false |
| get-function(functionname, css: false) | Return the specified function. If css is true, return the pure CSS function. |
| global-variable-exists(variablename) | Detect whether a global variable is defined. Example: variable-exists(a) Result: true |
| inspect(value) | Return a string representation; value is a Sass expression. |
| mixin-exists(mixinname) | Detect whether the specified mixin (mixinname) exists. Example: mixin-exists("important-text") Result: true |
| type-of(value) | Return the value type. The return value can be number, string, color, list, map, bool, null, function, arglist. Example: type-of(15px) Result: number type-of(#ff0000) Result: color |
| unit(number) | Return the unit (or compound unit) of the passed number. Example: unit(15px) Result: px |
| unitless(number) | Return a boolean value indicating whether the passed number has a unit. Example: unitless(15px) Result: false unitless(15) Result: true |
| variable-exists(variablename) | Determine whether a variable is in the current scope. Example: variable-exists(b) Result: true |
Other Extensions
Sass Functions