scanWhileRight

Scans from right, while a test passes. 📦 😺 🏃 📼 🌔 📜 📰 📘

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

array.scanWhileRight(x, ft);
// x:  an array
// ft: test function (v, i, x)
// → first index where test passes till end

const array = require("extra-array");

var x = [1, 1, 2, 2, 3, 3, 4, 4];
array.scanWhileRight(x, v => v % 3 !== 0);
// 6                       ^

array.scanWhileRight(x, v => v % 2 !== 0);
// 8                            ^

array.scanWhileRight(x, v => v % 6 !== 0);
// 0    ^

References

• List-Extra.elemIndex: elm
• iterable-binsearch: @krisselden
• binarysearch: @soldair