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node_modules/nth-check/README.md

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+# nth-check [![Build Status](https://travis-ci.org/fb55/nth-check.svg)](https://travis-ci.org/fb55/nth-check)
+
+A performant nth-check parser & compiler.
+
+### About
+
+This module can be used to parse & compile nth-checks, as they are found in CSS 3's `nth-child()` and `nth-last-of-type()`.
+
+`nth-check` focusses on speed, providing optimized functions for different kinds of nth-child formulas, while still following the [spec](http://www.w3.org/TR/css3-selectors/#nth-child-pseudo).
+
+### API
+
+```js
+var nthCheck = require("nth-check");
+```
+
+##### `nthCheck(formula)`
+
+First parses, then compiles the formula.
+
+##### `nthCheck.parse(formula)`
+
+Parses the expression, throws a `SyntaxError` if it fails, otherwise returns an array containing two elements.
+
+__Example:__
+
+```js
+nthCheck.parse("2n+3") //[2, 3]
+```
+
+##### `nthCheck.compile([a, b])`
+
+Takes an array with two elements (as returned by `.parse`) and returns a highly optimized function.
+
+If the formula doesn't match any elements, it returns [`boolbase`](https://github.com/fb55/boolbase)'s `falseFunc`, otherwise, a function accepting an _index_ is returned, which returns whether or not a passed _index_ matches the formula. (Note: The spec starts counting at `1`, the returned function at `0`).
+
+__Example:__
+```js
+var check = nthCheck.compile([2, 3]);
+
+check(0) //false
+check(1) //false
+check(2) //true
+check(3) //false
+check(4) //true
+check(5) //false
+check(6) //true
+```
+
+---
+License: BSD