ramda
Version:
A practical functional library for JavaScript programmers.
37 lines • 1.19 kB
JavaScript
var _curry2 = /*#__PURE__*/require("./internal/_curry2.js");
var _dispatchable = /*#__PURE__*/require("./internal/_dispatchable.js");
var _xfindIndex = /*#__PURE__*/require("./internal/_xfindIndex.js");
/**
* Returns the index of the first element of the list which matches the
* predicate, or `-1` if no element matches.
*
* Acts as a transducer if a transformer is given in list position.
*
* @func
* @memberOf R
* @since v0.1.1
* @category List
* @sig (a -> Boolean) -> [a] -> Number
* @param {Function} fn The predicate function used to determine if the element is the
* desired one.
* @param {Array} list The array to consider.
* @return {Number} The index of the element found, or `-1`.
* @see R.transduce, R.indexOf
* @example
*
* const xs = [{a: 1}, {a: 2}, {a: 3}];
* R.findIndex(R.propEq(2, 'a'))(xs); //=> 1
* R.findIndex(R.propEq(4, 'a'))(xs); //=> -1
*/
var findIndex = /*#__PURE__*/_curry2( /*#__PURE__*/_dispatchable([], _xfindIndex, function findIndex(fn, list) {
var idx = 0;
var len = list.length;
while (idx < len) {
if (fn(list[idx])) {
return idx;
}
idx += 1;
}
return -1;
}));
module.exports = findIndex;