scanUntilRight - nodef/extra-iterable GitHub Wiki

Scan from right, until a test passes.

Alternatives: scanWhile, scanWhileRight, scanUntil, scanUntilRight. Similar: search, [scan], find.

function scanUntilRight(x, ft)
// x:  an iterable
// ft: test function (v, i, x)
const xiterable = require('extra-iterable');

var x = [1, 1, 2, 2, 3, 3, 4, 4];
xiterable.scanUntilRight(x, v => v % 3 === 0);
// → 6                     ^

xiterable.scanUntilRight(x, v => v % 2 === 0);
// → 8                          ^

xiterable.scanUntilRight(x, v => v % 6 === 0);
// → 0  ^

References