.. | ||
compile.js | ||
index.js | ||
LICENSE | ||
package.json | ||
parse.js | ||
README.md |
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.
API
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:
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
'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:
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