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## Sass and SCSS Function Reference                 ##
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Contents:
RGB Functions__________________________________Line 19
HSL Functions__________________________________Line 29
Opacity Functions______________________________Line 45
Other Color Functions__________________________Line 52
String Functions_______________________________Line 63
Number Functions_______________________________Line 68
List Functions_________________________________Line 78
Introspective Functions________________________Line 85
Misc Functions_________________________________Line 92

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# Summary based on Official Sass/SCSS Documentation #
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// RGB FUNCTIONS //
rgb($red, $green, $blue)           // Converts an rgb(red, green, blue) triplet into a color.
rgba($red, $green, $blue, $alpha)  // Converts an rgba(red, green, blue, alpha) quadruplet into a color.
rgba($color, $alpha)               // Adds an alpha layer to any color value.
red($color)                        // Gets the red component of a color.
green($color)                      // Gets the green component of a color.
blue($color)                       // Gets the blue component of a color.
mix($color-1, $color-2, [$weight]) // Mixes two colors together.


// HSL FUNCTIONS //
hsl($hue, $saturation, $lightness)          // Converts an hsl(hue, saturation, lightness) triplet into a color.
hsla($hue, $saturation, $lightness, $alpha) // Converts an hsla(hue, saturation, lightness, alpha) quadruplet into a color.
hue($color)                                 // Gets the hue component of a color.
saturation($color)                          // Gets the saturation component of a color.
lightness($color)                           // Gets the lightness component of a color.
adjust-hue($color, $degrees)                // Changes the hue of a color.
lighten($color, $amount)                    // Makes a color lighter.
darken($color, $amount)                     // Makes a color darker.
saturate($color, $amount)                   // Makes a color more saturated.
desaturate($color, $amount)                 // Makes a color less saturated.
grayscale($color)                           // Converts a color to grayscale.
complement($color)                          // Returns the complement of a color.
invert($color)                              // Returns the inverse of a color.


// OPACITY FUNCTIONS //
alpha($color) / opacity($color)                             // Gets the alpha component (opacity) of a color.
rgba($color, $alpha)                                        // Add or change an alpha layer for any color value.
opacify($color, $amount) / fade-in($color, $amount)         // Makes a color more opaque.
transparentize($color, $amount) / fade-out($color, $amount) // Makes a color more transparent.


// OTHER COLOR FUNCTIONS //
adjust-color($color, [$red], [$green], [$blue], [$hue], [$saturation], [$lightness], [$alpha])
     // Increase or decrease any of the components of a color.
scale-color($color, [$red], [$green], [$blue], [$saturation], [$lightness], [$alpha])
     // Fluidly scale one or more components of a color.
change-color($color, [$red], [$green], [$blue], [$hue], [$saturation], [$lightness], [$alpha])
     // Changes one or more properties of a color.
ie-hex-str($color)
     // Converts a color into the format understood by IE filters.


// STRING FUNCTIONS //
unquote($string) // Removes the quotes from a string.
quote($string)   // Adds quotes to a string.


// NUMBER FUNCTIONS //
percentage($value) // Converts a unitless number to a percentage.
round($value)      // Rounds a number to the nearest whole number.
ceil($value)       // Rounds a number up to the nearest whole number.
floor($value)      // Rounds a number down to the nearest whole number.
abs($value)        // Returns the absolute value of a number.
min($x1, $x2, �)   // Finds the minimum of several values.
max($x1, $x2, �)   // Finds the maximum of several values.


// LIST FUNCTIONS //
length($list)                      // Returns the length of a list.
nth($list, $n)                     // Returns a specific item in a list.
join($list1, $list2, [$separator]) // Joins together two lists into one.
append($list1, $val, [$separator]) // Appends a single value onto the end of a list.


// INTROSPECTIVE FUNCTIONS //
type-of($value)                  // Returns the type of a value.
unit($number)                    // Returns the units associated with a number.
unitless($number)                // Returns whether a number has units or not.
comparable($number-1, $number-2) // Returns whether two numbers can be added or compared.


// MISC FUNCTIONS //
if($condition, $if-true, $if-false)  // Returns one of two values, depending on whether or not a condition is true.

http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html

A concise reference listing all of the available functions built into Sass.

Sass/SCSS Function Reference

css

SASS