The introspection functions in this group allow you to examine the state of Sass itself.
The introspection functions are rarely used when building a stylesheet. However, they are valuable if something does not work properly - to figure out what's going on: like debugging functions.
The following table lists all introspection functions in Sass:
| Function | Description | Examples | Result |
|---|---|---|---|
| variable-exists($name) | Returns a Boolean value indicating whether the specified variable exists, either globally or in the current scope | $a: 10px; | true |
| variable-exists($not-declared) | false | ||
| global-variable-exists($name) | Returns a Boolean value indicating whether the specified variable exists at the global level | $a: 10px; global-variable-exists(a); |
true |
| mixin-exists($name) | Returns a Boolean value indicating whether the specified mixin exists | @mixin text-color {color: red; } | true |
| inspect($value) | Returns $value as it is represented by Sass. | inspect(12) | "12" |
| type-of($value) | Returns a string containing the Sass data type of $value | type-of(1 2 3) | "list" |
| unit($number) | Returns the unit associated with a number, or an empty string if the number is unitless | $a: 10px; | "px" |
| $a: 10; | "" | ||
| unitless($number) | Returns a Boolean value indicating whether the specified number has a unit associated with it | $a: 10px; | false |
| comparable($number1, $number2) | Returns a Boolean value indicating whether the specified numbers can be added, subtracted or compared | comparable(1em, 4em) | true |
| comparable(1em, 3px) | false | ||
| comparable(1em, 5) | true |
