foop
Version:
interfaces that describe their intentions.
31 lines (30 loc) • 2.57 kB
JavaScript
/**
* Makes a comparator function out of a function that reports whether the first
* element is less than the second.
*
* @since 5.0.0-beta.5
* @memberOf sort
*
* @param {Function} predicate A predicate function of arity two which will return `true` if the first argument
* is less than the second, `false` otherwise
* @return {Function} A Function :: a -> b -> Int that returns `-1` if a < b, `1` if b < a, otherwise `0`
*
* @func
* @fork v0.1.0
* @category Function
* @sig (a, b -> Boolean) -> (a, b -> Number)
*
* @example
*
* var byAge = R.comparator((a, b) => a.age < b.age);
* var people = [
* // ...
* ];
* var peopleByIncreasingAge = R.sort(byAge, people);
*/
module.exports = function comparator(predicate) {
return function(a, b) {
return predicate(a, b) ? -1 : predicate(b, a) ? 1 : 0
}
}
//# sourceMappingURL=data:application/json;charset=utf-8;base64,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