javascript - Array.prototype.find, what's its spec? -

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those have chrome 30.0.1599.14 dev seem gifted of new function:

string(array.prototype.find); // "function find() { [native code] }"

however, haven't found reference addition. tests seems accepts arguments a-la some, every , on:

array.some(callback[, thisobject]);

and callback usual callback function of kind:

function([item[, index[, array]]]) {    ... }

the function expected return true when "right" item passed, item becomes value returned find. example:

array.prototype.slice.call(document.getelementsbytagname("*"))         .find(function(element) {return element.id === "content";});

it's odd way re-define document.getelementbyid, except when item isn't found find returns undefined instead of null.

it nice if function accept initial index, or if there dual function lastfind parses array end.

is there who's seen function , can tell me can find spec?

it ecma script 6. here's html version of es6 spec. here's specific section array.prototype.find().

update: also, the chromium bug array.prototype.find implementation.


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