filterAt

Keep values at given keys.

Alternatives: filterAt, filterAt$.
Similar: map, reduce, filter, filterAt, reject, rejectAt.

function filterAt(x, ks)
// x:  a map
// ks: keys

const map = require('extra-map');

var x = new Map([['a', 1], ['b', 2], ['c', 3], ['d', 4], ['e', 5]]);
map.filterAt(x, ['a', 'c', 'e']);
// → Map(3) { 'a' => 1, 'c' => 3, 'e' => 5 }

map.filterAt(x, ['b', 'd']);
// → Map(2) { 'b' => 2, 'd' => 4 }

References

• Data.List.filter: Haskell
• Array.prototype.filter: MDN web docs
• array_filter: PHP
• _.remove: lodash
• _.without: lodash
• _.compact: lodash
• _.pull: lodash
• _.pullAll: lodash
• _.pullAllBy: lodash
• _.pullAllWith: lodash
• Array.filter: sugarjs
• Array.exclude: sugarjs
• Array.compact: sugarjs
• array-tools.where: @75lb