LASS_or_you_DIE

﷽

❤️Announcement!❤️

###lass_css LASS Writing CSS fails

://?.com/Shinmera/LASS/blame/master/README.md

Examples

LASS supports two modes, one being directly in your lisp code, the other in pure LASS files. Adding LASS into your code is easy:

(lass:compile-and-write
 '(div
   :background black))

"div{
    background: black;
}"

LASS works on the following simple principles: A list is a block. The first argument in the list is a selector. The body of the list makes up the properties and sub-blocks. A property is started with a keyword that is used as the property name. Following is a bunch of property arguments until a new keyword, list, or the end is reached. A list inside a block is, again, a block with the twist that the parent block's selector is prepended to the sub-block's selector.

(lass:compile-and-write
 '(nav
   (ul
    :list-style none
    (li
     :margin 0 :padding 0
     :display inline-block)))))

"nav ul{
    list-style: none;
}

nav ul li{
    margin: 0;
    padding: 0;
    display: inline-block;
}"

Since LASS' COMPILE-SHEET simply takes a bunch of lists as its argument, you can use the backquote and comma to integrate variables from your lisp environment:

(let ((color "#0088EE"))
  (lass:compile-and-write
   `(div
     :background ,color))))

"div{
    background: #0088EE;
}"

Alternatively however, and this is especially useful in pure LASS files, you can use the LET block to create LASS-specific bindings:

(lass:compile-and-write
 '(:let ((color "#0088EE"))
   (div
    :background #(color))))

"div{
    background: #0088EE;
}"

LASS' selector mechanism is very flexible and allows for some complex logic to reduce duplication:

(lass:compile-and-write
 '(article
   ((:or p blockquote)
    :margin 0 :padding 0

    (a
     :color black)

    ((:and a :hover)
     :color darkred))))

"article p, article blockquote{
    margin: 0;
    padding: 0;
}

article p a, article blockquote a{
    color: black;
}

article p a:hover, article blockquote a:hover{
    color: darkred;
}"

But it can go even further:

    (lass:compile-and-write
     '((:and
        (:or article section)
        (:= data-author (:or yukari ran chen))
        (:nth-child (:or 1 2 3)))
       :display none))
    
    "article[data-author=\"yukari\"]:nth-child(1),
     article[data-author=\"yukari\"]:nth-child(2),
     article[data-author=\"yukari\"]:nth-child(3),
     article[data-author=\"ran\"]:nth-child(1),
     article[data-author=\"ran\"]:nth-child(2),
     article[data-author=\"ran\"]:nth-child(3),
     article[data-author=\"chen\"]:nth-child(1),
     article[data-author=\"chen\"]:nth-child(2),
     article[data-author=\"chen\"]:nth-child(3),
     section[data-author=\"yukari\"]:nth-child(1),
     section[data-author=\"yukari\"]:nth-child(2),
     section[data-author=\"yukari\"]:nth-child(3),
     section[data-author=\"ran\"]:nth-child(1),
     section[data-author=\"ran\"]:nth-child(2),
     section[data-author=\"ran\"]:nth-child(3),
     section[data-author=\"chen\"]:nth-child(1),
     section[data-author=\"chen\"]:nth-child(2),
     section[data-author=\"chen\"]:nth-child(3){
        display: none;
    }"

Whoa nelly!

Some CSS properties are not fully specified yet and require browser-specific prefixes. LASS can help you with that, too:

    (lass:compile-and-write
     '(.fun
       :linear-gradient "deg(45)" black 0% darkgray 100%
       :transform rotate -45deg))
    
    ".fun{
        background: -moz-linear-gradient(deg(45), black 0%, darkgray 100%);
        background: -o-linear-gradient(deg(45), black 0%, darkgray 100%);
        background: -webkit-linear-gradient(deg(45), black 0%, darkgray 100%);
        background: -ms-linear-gradient(deg(45), black 0%, darkgray 100%);
        background: linear-gradient(deg(45), black 0%, darkgray 100%);
        -moz-transform: rotate(-45deg);
        -o-transform: rotate(-45deg);
        -webkit-transform: rotate(-45deg);
        -ms-transform: rotate(-45deg);
        transform: rotate(-45deg);
    }"

LASS also supports the various @QUERY operator blocks:

(lass:compile-and-write
 '(:media "(max-width: 800px)"
   (div
    :margin 0)))

"@media (max-width: 800px){
    div{
        margin: 0;
    }
}"

By default LASS activates pretty-printing and inserts newlines and spaces where appropriate in order to make the result readable and easy to debug. However, you can also deactivate that and directly produce minified CSS:

(let ((lass:*pretty* NIL))
  (lass:compile-and-write
   '(:media "(max-width: 800px)"
     (div
      :margin 0))))

"@media (max-width: 800px){div{margin:0;}}"

As mentioned above you can write pure LASS files to compile down to a CSS file. To do that, simply M-x xah-fly-save-buffer-if-file

://?.com/Shinmera/LASS/blame/master/README.md