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diff --git a/vendors/lessphp/docs/docs.md b/vendors/lessphp/docs/docs.md deleted file mode 100644 index c46ad0fe1..000000000 --- a/vendors/lessphp/docs/docs.md +++ /dev/null @@ -1,1168 +0,0 @@ - title: v0.3.5 documentation - link_to_home: true --- - -<h2 skip="true">Documentation v0.3.5</h2> - -<div style="margin-bottom: 1em;">$index</div> - -**lessphp** is a compiler that generates CSS from a superset language which -adds a collection of convenient features often seen in other languages. All CSS -is compatible with LESS, so you can start using new features with your existing CSS. - -It is designed to be compatible with [less.js](http://lesscss.org), and suitable -as a drop in replacement for PHP projects. - -## Getting Started - -The homepage for **lessphp** can be found at [http://leafo.net/lessphp/][1]. - -You can follow development at the project's [GitHub][2]. - -Including **lessphp** in your project is as simple as dropping the single -include file into your code base and running the appropriate compile method as -described in the [PHP Interface](#php_interface). - - [1]: http://leafo.net/lessphp "lessphp homepage" - [2]: https://github.com/leafo/lessphp "lessphp GitHub page" - -## Installation - -**lessphp** is distributed entirely in a single stand-alone file. Download the -latest version from either [the homepage][1] or [GitHub][2]. - -Development versions can also be downloading from GitHub. - -Place `lessphp.inc.php` in a location available to your PHP scripts, and -include it. That's it! you're ready to begin. - -## The Language - -**lessphp** is very easy to learn because it generally functions how you would -expect it to. If you feel something is challenging or missing, feel free to -open an issue on the [bug tracker](https://github.com/leafo/lessphp/issues). - -It is also easy to learn because any standards-compliant CSS code is valid LESS -code. You are free to gradually enhance your existing CSS code base with LESS -features without having to worry about rewriting anything. - -The following is a description of the new languages features provided by LESS. - -### Line Comments - -Simple but very useful; line comments are started with `//`: - - ```less - // this is a comment - body { - color: red; // as is this - /* block comments still work also */ - } - ``` - -### Variables -Variables are identified with a name that starts with `@`. To declare a -variable, you create an appropriately named CSS property and assign it a value: - - ```less - @family: "verdana"; - @color: red; - body { - @mycolor: red; - font-family: @family; - color: @color; - border-bottom: 1px solid @color; - } - ``` - -Variable declarations will not appear in the output. Variables can be declared -in the outer most scope of the file, or anywhere else a CSS property may -appear. They can hold any CSS property value. - -Variables are only visible for use from their current scope, or any enclosed -scopes. - -If you have a string or keyword in a variable, you can reference another -variable by that name by repeating the `@`: - - ```less - @value: 20px; - @value_name: "value"; - - width: @@value_name; - ``` - -### Expressions - -Expressions let you combine values and variables in meaningful ways. For -example you can add to a color to make it a different shade. Or divide up the -width of your layout logically. You can even concatenate strings. - -Use the mathematical operators to evaluate an expression: - - ```less - @width: 960px; - .nav { - width: @width / 3; - color: #001 + #abc; - } - .body { - width: 2 * @width / 3; - font-family: "hel" + "vetica"; - } - ``` - -Parentheses can be used to control the order of evaluation. They can also be -used to force an evaluation for cases where CSS's syntax makes the expression -ambiguous. - -The following property will produce two numbers, instead of doing the -subtraction: - - ```less - margin: 10px -5px; - ``` - -To force the subtraction: - - ```less - margin: (10px -5px); - ``` - -It is also safe to surround mathematical operators by spaces to ensure that -they are evaluated: - - ```less - margin: 10px - 5px; - ``` - -Division has a special quirk. There are certain CSS properties that use the `/` -operator as part of their value's syntax. Namely, the [font][4] shorthand and -[border-radius][3]. - - [3]: https://developer.mozilla.org/en/CSS/border-radius - [4]: https://developer.mozilla.org/en/CSS/font - - -Thus, **lessphp** will ignore any division in these properties unless it is -wrapped in parentheses. For example, no division will take place here: - - ```less - .font { - font: 20px/80px "Times New Roman"; - } - ``` - -In order to force division we must wrap the expression in parentheses: - - ```less - .font { - font: (20px/80px) "Times New Roman"; - } - ``` - -If you want to write a literal `/` expression without dividing in another -property (or a variable), you can use [string unquoting](#string_unquoting): - - ```less - .var { - @size: ~"20px/80px"; - font: @size sans-serif; - } - ``` - -### Nested Blocks - -By nesting blocks we can build up a chain of CSS selectors through scope -instead of repeating them. In addition to reducing repetition, this also helps -logically organize the structure of our CSS. - - ```less - ol.list { - li.special { - border: 1px solid red; - } - - li.plain { - font-weight: bold; - } - } - ``` - - -This will produce two blocks, a `ol.list li.special` and `ol.list li.plain`. - -Blocks can be nested as deep as required in order to build a hierarchy of -relationships. - -The `&` operator can be used in a selector to represent its parent's selector. -If the `&` operator is used, then the default action of appending the parent to -the front of the child selector separated by space is not performed. - - ```less - b { - a & { - color: red; - } - - // the following have the same effect - - & i { - color: blue; - } - - i { - color: blue; - } - } - ``` - - -Because the `&` operator respects the whitespace around it, we can use it to -control how the child blocks are joined. Consider the differences between the -following: - - ```less - div { - .child-class { color: purple; } - - &.isa-class { color: green; } - - #child-id { height: 200px; } - - &#div-id { height: 400px; } - - &:hover { color: red; } - - :link { color: blue; } - } - ``` - -The `&` operator also works with [mixins](#mixins), which produces interesting results: - - ```less - .within_box_style() { - .box & { - color: blue; - } - } - - #menu { - .within_box_style; - } - ``` - -### Mixins - -Any block can be mixed in just by naming it: - - ```less - .mymixin { - color: blue; - border: 1px solid red; - - .special { - font-weight: bold; - } - } - - - h1 { - font-size: 200px; - .mixin; - } - ``` - -All properties and child blocks are mixed in. - -Mixins can be made parametric, meaning they can take arguments, in order to -enhance their utility. A parametric mixin all by itself is not outputted when -compiled. Its properties will only appear when mixed into another block. - -The canonical example is to create a rounded corners mixin that works across -browsers: - - ```less - .rounded-corners(@radius: 5px) { - border-radius: @radius; - -webkit-border-radius: @radius; - -moz-border-radius: @radius; - } - - .header { - .rounded-corners(); - } - - .info { - background: red; - .rounded-corners(14px); - } - ``` - -If you have a mixin that doesn't have any arguments, but you don't want it to -show up in the output, give it a blank argument list: - - ```less - .secret() { - font-size: 6000px; - } - - .div { - .secret; - } - ``` - -If the mixin doesn't need any arguments, you can leave off the parentheses when -mixing it in, as seen above. - -You can also mixin a block that is nested inside other blocks. You can think of -the outer block as a way of making a scope for your mixins. You just list the -names of the mixins separated by spaces, which describes the path to the mixin -you want to include. Optionally you can separate them by `>`. - - ```less - .my_scope { - .some_color { - color: red; - .inner_block { - text-decoration: underline; - } - } - .bold { - font-weight: bold; - color: blue; - } - } - - .a_block { - .my_scope .some_color; - .my_scope .some_color .inner_block; - } - - .another_block { - // the alternative syntax - .my_scope > .bold; - } - ``` - -#### `@arguments` Variable - -Within an mixin there is a special variable named `@arguments` that contains -all the arguments passed to the mixin along with any remaining arguments that -have default values. The value of the variable has all the values separated by -spaces. - -This useful for quickly assigning all the arguments: - - ```less - .box-shadow(@x, @y, @blur, @color) { - box-shadow: @arguments; - -webkit-box-shadow: @arguments; - -moz-box-shadow: @arguments; - } - .menu { - .box-shadow(1px, 1px, 5px, #aaa); - } - ``` - -In addition to the arguments passed to the mixin, `@arguments` will also include -remaining default values assigned by the mixin: - - - ```less - .border-mixin(@width, @style: solid, @color: black) { - border: @arguments; - } - - pre { - .border-mixin(4px, dotted); - } - - ``` - - -#### Pattern Matching - -When you *mix in* a mixin, all the available mixins of that name in the current -scope are checked to see if they match based on what was passed to the mixin -and how it was declared. - -The simplest case is matching by number of arguments. Only the mixins that -match the number of arguments passed in are used. - - ```less - .simple() { // matches no arguments - height: 10px; - } - - .simple(@a, @b) { // matches two arguments - color: red; - } - - .simple(@a) { // matches one argument - color: blue; - } - - div { - .simple(10); - } - - span { - .simple(10, 20); - } - ``` - -Whether an argument has default values is also taken into account when matching -based on number of arguments: - - ```less - // matches one or two arguments - .hello(@a, @b: blue) { - height: @a; - color: @b; - } - - .hello(@a, @b) { // matches only two - width: @a; - border-color: @b; - } - - .hello(@a) { // matches only one - padding: 1em; - } - - div { - .hello(10px); - } - - pre { - .hello(10px, yellow); - } - ``` - -Additionally, a *vararg* value can be used to further control how things are -matched. A mixin's argument list can optionally end in the special argument -named `...`. The `...` may match any number of arguments, including 0. - - ```less - // this will match any number of arguments - .first(...) { - color: blue; - } - - // matches at least 1 argument - .second(@arg, ...) { - height: 200px + @arg; - } - - div { .first("some", "args"); } - pre { .second(10px); } - ``` - -If you want to capture the values that get captured by the *vararg* you can -give it a variable name by putting it directly before the `...`. This variable -must be the last argument defined. It's value is just like the special -[`@arguments` variable](#arguments_variable), a space separated list. - - - ```less - .hello(@first, @rest...) { - color: @first; - text-shadow: @rest; - } - - span { - .hello(red, 1px, 1px, 0px, white); - } - - ``` - -Another way of controlling whether a mixin matches is by specifying a value in -place of an argument name when declaring the mixin: - - ```less - .style(old, @size) { - font: @size serif; - } - - .style(new, @size) { - font: @size sans-serif; - } - - .style(@_, @size) { - letter-spacing: floor(@size / 6px); - } - - em { - @switch: old; - .style(@switch, 15px); - } - ``` - -Notice that two of the three mixins were matched. The mixin with a matching -first argument, and the generic mixin that matches two arguments. It's common -to use `@_` as the name of a variable we intend to not use. It has no special -meaning to LESS, just to the reader of the code. - -#### Guards - -Another way of restricting when a mixin is mixed in is by using guards. A guard -is a special expression that is associated with a mixin declaration that is -evaluated during the mixin process. It must evaluate to true before the mixin -can be used. - -We use the `when` keyword to begin describing a list of guard expressions. - -Here's a simple example: - - ```less - .guarded(@arg) when (@arg = hello) { - color: blue; - } - - div { - .guarded(hello); // match - } - - span { - .guarded(world); // no match - } - ``` -Only the `div`'s mixin will match in this case, because the guard expression -requires that `@arg` is equal to `hello`. - -We can include many different guard expressions by separating them by commas. -Only one of them needs to match to trigger the mixin: - - ```less - .x(@a, @b) when (@a = hello), (@b = world) { - width: 960px; - } - - div { - .x(hello, bar); // match - } - - span { - .x(foo, world); // match - } - - pre { - .x(foo, bar); // no match - } - ``` - -Instead of a comma, we can use `and` keyword to make it so all of the guards -must match in order to trigger the mixin. `and` has higher precedence than the -comma. - - ```less - .y(@a, @b) when (@a = hello) and (@b = world) { - height: 600px; - } - - div { - .y(hello, world); // match - } - - span { - .y(hello, bar); // no match - } - ``` - -Commas and `and`s can be mixed and matched. - -You can also negate a guard expression by using `not` in from of the parentheses: - - ```less - .x(@a) when not (@a = hello) { - color: blue; - } - - div { - .x(hello); // no match - } - ``` - -The `=` operator is used to check equality between any two values. For numbers -the following comparison operators are also defined: - -`<`, `>`, `=<`, `>=` - -There is also a collection of predicate functions that can be used to test the -type of a value. - -These are `isnumber`, `iscolor`, `iskeyword`, `isstring`, `ispixel`, -`ispercentage` and `isem`. - - ```less - .mix(@a) when (ispercentage(@a)) { - height: 500px * @a; - } - .mix(@a) when (ispixel(@a)) { - height: @a; - } - - div.a { - .mix(50%); - } - - div.a { - .mix(350px); - } - ``` - -#### !important - -If you want to apply the `!important` suffix to every property when mixing in a -mixin, just append `!important` to the end of the call to the mixin: - - ```less - .make_bright { - color: red; - font-weight: bold; - } - - .color { - color: green; - } - - body { - .make_bright() !important; - .color(); - } - - ``` - -### Selector Expressions - -Sometimes we want to dynamically generate the selector of a block based on some -variable or expression. We can do this by using *selector expressions*. Selector -expressions are CSS selectors that are evaluated in the current scope before -being written out. - -A simple example is a mixin that dynamically creates a selector named after the -mixin's argument: - - ```less - .create-selector(@name) { - (e(@name)) { - color: red; - } - } - - .create-selector("hello"); - .create-selector("world"); - ``` - -Any selector that is enclosed in `()` will have it's contents evaluated and -directly written to output. The value is not changed any way before being -outputted, thats why we use the `e` function. If you're not familiar, the `e` -function strips quotes off a string value. If we didn't have it, then the -selector would have quotes around it, and that's not valid CSS! - -Any value can be used in a selector expression, but it works best when using -strings and things like [String Interpolation](#string_interpolation). - -Here's an interesting example adapted from Twitter Bootstrap. A couple advanced -things are going on. We are using [Guards](#guards) along with a recursive -mixin to work like a loop to generate a series of CSS blocks. - - - ```less - // create our recursive mixin: - .spanX (@index) when (@index > 0) { - (~".span@{index}") { - width: @index * 100px; - } - .spanX(@index - 1); - } - .spanX (0) {} - - // mix it into the global scopee: - .spanX(4); - ``` - -### Import - -Multiple LESS files can be compiled into a single CSS file by using the -`@import` statement. Be careful, the LESS import statement shares syntax with -the CSS import statement. If the file being imported ends in a `.less` -extension, or no extension, then it is treated as a LESS import. Otherwise it -is left alone and outputted directly: - - ```less - // my_file.less - .some-mixin(@height) { - height: @height; - } - - // main.less - @import "main.less" // will import the file if it can be found - @import "main.css" // will be left alone - - body { - .some-mixin(400px); - } - ``` - -All of the following lines are valid ways to import the same file: - - ```less - @import "file"; - @import 'file.less'; - @import url("file"); - @import url('file'); - @import url(file); - ``` - -When importing, the `importDir` is searched for files. This can be configured, -see [PHP Interface](#php_interface). - -### String Interpolation - -String interpolation is a convenient way to insert the value of a variable -right into a string literal. Given some variable named `@var_name`, you just -need to write it as `@{var_name}` from within the string to have its value -inserted: - - ```less - @symbol: ">"; - h1:before { - content: "@{symbol}: "; - } - - h2:before { - content: "@{symbol}@{symbol}: "; - } - ``` - -There are two kinds of strings, implicit and explicit strings. Explicit strings -are wrapped by double quotes, `"hello I am a string"`, or single quotes `'I am -another string'`. Implicit strings only appear when using `url()`. The text -between the parentheses is considered a string and thus string interpolation is -possible: - - ```less - @path: "files/"; - body { - background: url(@{path}my_background.png); - } - ``` - -### String Format Function - -The `%` function can be used to insert values into strings using a *format -string*. It works similar to `printf` seen in other languages. It has the -same purpose as string interpolation above, but gives explicit control over -the output format. - - ```less - @symbol: ">"; - h1:before { - content: %("%s: ", @symbol); - } - ``` - -The `%` function takes as its first argument the format string, following any -number of addition arguments that are inserted in place of the format -directives. - -A format directive starts with a `%` and is followed by a single character that -is either `a`, `d`, or `s`: - - ```less - strings: %("%a %d %s %a", hi, 1, 'ok', 'cool'); - ``` - -`%a` and `%d` format the value the same way: they compile the argument to its -CSS value and insert it directly. When used with a string, the quotes are -included in the output. This typically isn't what we want, so we have the `%s` -format directive which strips quotes from strings before inserting them. - -The `%d` directive functions the same as `%a`, but is typically used for numbers -assuming the output format of numbers might change in the future. - -### String Unquoting - -Sometimes you will need to write proprietary CSS syntax that is unable to be -parsed. As a workaround you can place the code into a string and unquote it. -Unquoting is the process of outputting a string without its surrounding quotes. -There are two ways to unquote a string. - -The `~` operator in front of a string will unquote that string: - - ```less - .class { - // a made up, but problematic vendor specific CSS - filter: ~"Microsoft.AlphaImage(src='image.png')"; - } - ``` - -If you are working with other types, such as variables, there is a built in -function that let's you unquote any value. It is called `e`. - - ```less - @color: "red"; - .class { - color: e(@color); - } - ``` - -### Built In Functions - -**lessphp** has a collection of built in functions: - -* `e(str)` -- returns a string without the surrounding quotes. - See [String Unquoting](#string_unquoting) - -* `floor(number)` -- returns the floor of a numerical input -* `round(number)` -- returns the rounded value of numerical input - -* `lighten(color, percent)` -- lightens `color` by `percent` and returns it -* `darken(color, percent)` -- darkens `color` by `percent` and returns it - -* `saturate(color, percent)` -- saturates `color` by `percent` and returns it -* `desaturate(color, percent)` -- desaturates `color` by `percent` and returns it - -* `fadein(color, percent)` -- makes `color` less transparent by `percent` and returns it -* `fadeout(color, percent)` -- makes `color` more transparent by `percent` and returns it - -* `spin(color, amount)` -- returns a color with `amount` degrees added to hue - -* `fade(color, amount)` -- returns a color with the alpha set to `amount` - -* `hue(color)` -- returns the hue of `color` - -* `saturation(color)` -- returns the saturation of `color` - -* `lightness(color)` -- returns the lightness of `color` - -* `alpha(color)` -- returns the alpha value of `color` or 1.0 if it doesn't have an alpha - -* `percentage(number)` -- converts a floating point number to a percentage, e.g. `0.65` -> `65%` - -* `mix(color1, color1, percent)` -- mixes two colors by percentage where 100% - keeps all of `color1`, and 0% keeps all of `color2`. Will take into account - the alpha of the colors if it exists. See - <http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#mix-instance_method>. - -* `rgbahex(color)` -- returns a string containing 4 part hex color. - - This is used to convert a CSS color into the hex format that IE's filter - method expects when working with an alpha component. - - ```less - .class { - @start: rgbahex(rgba(25, 34, 23, .5)); - @end: rgbahex(rgba(85, 74, 103, .6)); - // abridged example - -ms-filter: - e("gradient(start=@{start},end=@{end})"); - } - ``` - -## PHP Interface - -The PHP interface lets you control the compiler from your PHP scripts. There is -only one file to include to get access to everything: - - ```php - <?php - include "lessc.inc.php"; - ``` - -To compile a file to a string (of CSS code): - - ```php - $less = new lessc("myfile.less"); - $css = $less->parse(); - ``` - -To compile a string to a string: - - ```php - $less = new lessc(); // a blank lessc - $css = $less->parse("body { a { color: red } }"); - ``` - -### Output Formatting - -Besides the default output formatter, **lessphp** comes with two additional -ones, and it's easy to make your own. - -The first extra formatter is called `compressed`. It compresses the output by -removing any extra whitespace. - -We use the `setFormatter` method set the formatter that should be used. Just -pass the name of the formatter: - - ```php - $less = new lessc("myfile.less"); - - $less->setFormatter("compressed"); - - $css = $less->parse(); - ``` - -The second formatter is called `indent`. It will indent CSS blocks based on how -they were nested in the LESS code. - -#### Custom Formatter - -The easiest way to customize is to create your own instance of the formatter -and alter its public properties before passing it off to **lessphp**. The -`setFormatter` method can also take an instance of a formatter. - -For example, let's use tabs instead of the default two spaces to indent: - - ```php - $formatter = new lessc_formatter; - $formatter->indentChar = "\t"; - - $less = new lessc("myfile.less"); - $less->setFormatter($formatter); - $css = $less->parse(); - ``` - -For more information about what can be configured with the formatter consult -the sourcecode. - -### Compiling Automatically - -Often, you want to write the compiled CSS to a file, and only recompile when -the original LESS file has changed. The following function will check if the -modification date of the LESS file is more recent than the CSS file. The LESS -file will be compiled if it is. If the CSS file doesn't exist yet, then it will -also compile the LESS file. - - ```php - lessc::ccompile('myfile.less', 'mystyle.css'); - ``` - -`ccompile` is very basic, it only checks if the input file's modification time. -It is not of any files that are brought in using `@import`. - -For this reason we also have `lessc::cexecute`. It functions slightly -differently, but gives us the ability to check changes to all files used during -the compile. It takes one argument, either the name of the file we want to -compile, or an existing *cache object*. Its return value is an updated cache -object. - -If we don't have a cache object, then we call the function with the name of the -file to get the initial cache object. If we do have a cache object, then we -call the function with it. In both cases, an updated cache object is returned. - -The cache object keeps track of all the files that must be checked in order to -determine if a rebuild is required. - -The cache object is a plain PHP `array`. It stores the last time it compiled in -`$cache['updated']` and output of the compile in `$cache['compiled']`. - -Here we demonstrate creating an new cache object, then using it to see if we -have a recompiled version available to be written: - - - ```php - $less_file = 'myfile.less'; - $css_file = 'myfile.css'; - - // create a new cache object, and compile - $cache = lessc::cexecute('myfile.less'); - file_put_contents($css_file, $cache['compiled']); - - // the next time we run, write only if it has updated - $last_updated = $cache['updated']; - $cache = lessc::cexecute($cache); - if ($cache['updated'] > $last_updated) { - file_put_contents($css_file, $cache['compiled']); - } - - ``` - -In order for the system to fully work, we must save cache object between -requests. Because it's a plain PHP `array`, it's sufficient to -[`serialize`](http://php.net/serialize) it and save it the string somewhere -like a file or in persistent memory. - -An example with saving cache object to a file: - - ```php - function auto_compile_less($less_fname, $css_fname) { - // load the cache - $cache_fname = $less_fname.".cache"; - if (file_exists($cache_fname)) { - $cache = unserialize(file_get_contents($cache_fname)); - } else { - $cache = $less_fname; - } - - $new_cache = lessc::cexecute($cache); - if (!is_array($cache) || $new_cache['updated'] > $cache['updated']) { - file_put_contents($cache_fname, serialize($new_cache)); - file_put_contents($css_fname, $new_cache['compiled']); - } - } - - auto_compile_less('myfile.less', 'myfile.css'); - ``` - -`lessc:cexecute` takes an optional second argument, `$force`. Passing in true -will cause the input to always be recompiled. - -### Error Handling - -All of the following methods will throw an `Exception` if the parsing fails: - - ```php - $less = new lessc(); - try { - $less->parse("} invalid LESS }}}"); - } catch (Exception $ex) { - echo "lessphp fatal error: ".$ex->getMessage(); - } - ``` -### Setting Variables From PHP - -The `parse` function takes a second optional argument. If you want to -initialize variables from outside the LESS file then you can pass in an -associative array of names and values. The values will parsed as CSS values: - - ```php - $less = new lessc(); - echo $less->parse(".magic { color: @color; width: @base - 200; }", - array( - 'color' => 'red'; - 'base' => '960px'; - )); - ``` - -You can also do this when loading from a file. If the first argument of `parse` -is an array it will be used an array of variables to set. - - ```php - $less = new lessc("myfile.less"); - echo $less->parse(array('color' => 'blue')); - ``` - -### Custom Functions - -**lessphp** has a simple extension interface where you can implement user -functions that will be exposed in LESS code during the compile. They can be a -little tricky though because you need to work with the **lessphp** type system. - -An instance of `lessc`, the **lessphp** compiler has two relevant methods: -`registerFunction` and `unregisterFunction`. `registerFunction` takes two -arguments, a name and a callable value. `unregisterFunction` just takes the -name of an existing function to remove. - -Here's an example that adds a function called `double` that doubles any numeric -argument: - - ```php - <?php - include "lessc.inc.php"; - - function lessphp_double($arg) { - list($type, $value) = $arg; - return array($type, $value*2); - } - - $myless = new myless(); - $myless->registerFunction("double", "lessphp_double"); - - // gives us a width of 800px - echo $myless->parse("div { width: double(400px); }"); - ``` - -The second argument to `registerFunction` is any *callable value* that is -understood by [`call_user_func`](http://php.net/call_user_func). - -If we are using PHP 5.3 or above then we are free to pass a function literal -like so: - - ```php - $myless->registerFunction("double", function($arg) { - list($type, $value) = $arg; - return array($type, $value*2); - }); - ``` - -Now let's talk about the `double` function itself. - -Although a little verbose, the implementation gives us some insight on the type -system. All values in **lessphp** are stored in an array where the 0th element -is a string representing the type, and the other elements make up the -associated data for that value. - -The best way to get an understanding of the system is to register is dummy -function which does a `vardump` on the argument. Try passing the function -different values from LESS and see what the results are. - -The return value of the registered function must also be a **lessphp** type, but if it is -a string or numeric value, it will automatically be coerced into an appropriate -typed value. In our example, we reconstruct the value with our modifications -while making sure that we preserve the original type. - -In addition to the arguments passed from **lessphp**, the instance of -**lessphp** itself is sent to the registered function as the second argument. - -## Command Line Interface - -**lessphp** comes with a command line script written in PHP that can be used to -invoke the compiler from the terminal. On Linux an OSX, all you need to do is -place `plessc` and `lessc.inc.php` somewhere in your PATH (or you can run it in -the current directory as well). On windows you'll need a copy of `php.exe` to -run the file. To compile a file, `input.less` to CSS, run: - - ```bash - $ plessc input.less - ``` - -To write to a file, redirect standard out: - - ```bash - $ plessc input.less > output.css - ``` - -To compile code directly on the command line: - - ```bash - $ plessc -r "@color: red; body { color: @color; }" - ``` - -To watch a file for changes, and compile it as needed, use the `-w` flag: - - ```bash - $ plessc -w input-file output-file - ``` - -Errors from watch mode are written to standard out. - - -## License - -Copyright (c) 2010 Leaf Corcoran, <http://leafo.net/lessphp> - -Permission is hereby granted, free of charge, to any person obtaining -a copy of this software and associated documentation files (the -"Software"), to deal in the Software without restriction, including -without limitation the rights to use, copy, modify, merge, publish, -distribute, sublicense, and/or sell copies of the Software, and to -permit persons to whom the Software is furnished to do so, subject to -the following conditions: - -The above copyright notice and this permission notice shall be -included in all copies or substantial portions of the Software. - -THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, -EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF -MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND -NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE -LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION -OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION -WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. - - -*Also under GPL3 if required, see `LICENSE` file* - |