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node_modules/CSSselect/README.md

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+#CSSselect [![Build Status](https://secure.travis-ci.org/fb55/CSSselect.png?branch=master)](http://travis-ci.org/fb55/CSSselect)
+
+a CSS selector compiler/engine
+
+##What?
+
+CSSselect turns CSS selectors into functions that tests if elements match them. When searching for elements, testing is executed "from the top", similar to how browsers execute CSS selectors.
+
+In its default configuration, CSSselect queries the DOM structure of the [`domhandler`](https://github.com/fb55/domhandler) module.
+
+##API
+
+```js
+var CSSselect = require("CSSselect");
+```
+
+####`CSSselect(query, elems)`
+
+- `query` can be either a function or a string. If it's a string, the string is compiled as a CSS selector.
+- `elems` can be either an array of elements, or a single element. If it is an element, its children will be used (so we're working with an array again).
+
+Queries `elems`, returns an array containing all matches.
+
+Aliases: `CSSselect.selectAll(query, elems)`, `CSSselect.iterate(query, elems)`.
+
+####`CSSselect.compile(query)`
+
+Compiles the query, returns the function.
+
+####`CSSselect.is(elem, query)`
+
+Tests whether or not an element is matched by `query`. `query` can be either a CSS selector or a function.
+
+####`CSSselect.selectOne(query, elems)`
+
+Arguments are the same as for `CSSselect(query, elems)`. Only returns the first match, or `null` if there was no match.
+
+##Why?
+
+The common approach of executing CSS selectors (used eg. by [`Sizzle`](https://github.com/jquery/sizzle), [`nwmatcher`](https://github.com/dperini/nwmatcher/) and [`qwery`](https://github.com/ded/qwery)) is to execute every component of the selector in order, from left to right. The selector `a b` for example will first look for `a` elements, then search these for `b` elements.
+
+While this works, it has some downsides: Children of `a`s will be checked multiple times, first, to check if they are also `a`s, then, for every superior `a` once, if they are `b`s. Using [Big O notation](http://en.wikipedia.org/wiki/Big_O_notation), that would be `O(n^2)`.
+
+The far more efficient approach is to first look for `b` elements, then check if they have superior `a` elements: Using big O notation again, that would be `O(n)`.
+
+And that's exactly what CSSselect does.
+
+##How?
+
+By stacking functions!
+
+_//TODO: Better explanation. For now, if you're interested, have a look at the source code._
+
+
+---
+
+License: BSD-like