/**

* @fileoverview Various collections utility.

* @license Apache-2.0

*/

/** Makes a unique map. Typically used to track contextual type arguemnts. */

export function uniqueMap<K,V>(original: Map<K,V> | null = null, overrides: Map<K,V> | null = null): Map<K,V> {

var cloned = new Map<K,V>();

if (original) {

// TODO: for (let [k, v] of original) {

for (let _keys = Map_keys(original), i = 0, k = _keys.length; i < k; ++i) {

let k = unchecked(_keys[i]);

let v = assert(original.get(k));

cloned.set(k, v);

}

}

if (overrides) {

// TODO: for (let [k, v] of overrides) {

for (let _keys = Map_keys(overrides), i = 0, k = _keys.length; i < k; ++i) {

let k = unchecked(_keys[i]);

let v = assert(overrides.get(k));

cloned.set(k, v);

}

}

return cloned;

}