hasPrefix (original) (raw)
Examine if array starts with a prefix.
Similar: randomPrefix, prefixes, hasPrefix.
Similar: hasValue, hasPrefix, hasInfix, hasSuffix, hasSubsequence, hasPermutation, hasPath.
function hasPrefix(x, y, fc, fm) // x: an array // y: search prefix // fc: compare function (a, b) // fm: map function (v, i, x)
const xarray = require('extra-array');
var x = [1, 2, 3, 4]; xarray.hasPrefix(x, [1, 2]); // → true
xarray.hasPrefix(x, [-1, -2]); // → false
xarray.hasPrefix(x, [-1, -2], (a, b) => Math.abs(a) - Math.abs(b)); // → true
xarray.hasPrefix(x, [-1, -2], null, v => Math.abs(v)); // → true