luhn-generator
Version:
A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm
86 lines (83 loc) • 2.79 kB
JavaScript
;
var redefineAll = require('./_redefine-all');
var getWeak = require('./_meta').getWeak;
var anObject = require('./_an-object');
var isObject = require('./_is-object');
var anInstance = require('./_an-instance');
var forOf = require('./_for-of');
var createArrayMethod = require('./_array-methods');
var $has = require('./_has');
var validate = require('./_validate-collection');
var arrayFind = createArrayMethod(5);
var arrayFindIndex = createArrayMethod(6);
var id = 0;
// fallback for uncaught frozen keys
var uncaughtFrozenStore = function (that) {
return that._l || (that._l = new UncaughtFrozenStore());
};
var UncaughtFrozenStore = function () {
this.a = [];
};
var findUncaughtFrozen = function (store, key) {
return arrayFind(store.a, function (it) {
return it[0] === key;
});
};
UncaughtFrozenStore.prototype = {
get: function (key) {
var entry = findUncaughtFrozen(this, key);
if (entry) return entry[1];
},
has: function (key) {
return !!findUncaughtFrozen(this, key);
},
set: function (key, value) {
var entry = findUncaughtFrozen(this, key);
if (entry) entry[1] = value;
else this.a.push([key, value]);
},
'delete': function (key) {
var index = arrayFindIndex(this.a, function (it) {
return it[0] === key;
});
if (~index) this.a.splice(index, 1);
return !!~index;
}
};
module.exports = {
getConstructor: function (wrapper, NAME, IS_MAP, ADDER) {
var C = wrapper(function (that, iterable) {
anInstance(that, C, NAME, '_i');
that._t = NAME; // collection type
that._i = id++; // collection id
that._l = undefined; // leak store for uncaught frozen objects
if (iterable != undefined) forOf(iterable, IS_MAP, that[ADDER], that);
});
redefineAll(C.prototype, {
// 23.3.3.2 WeakMap.prototype.delete(key)
// 23.4.3.3 WeakSet.prototype.delete(value)
'delete': function (key) {
if (!isObject(key)) return false;
var data = getWeak(key);
if (data === true) return uncaughtFrozenStore(validate(this, NAME))['delete'](key);
return data && $has(data, this._i) && delete data[this._i];
},
// 23.3.3.4 WeakMap.prototype.has(key)
// 23.4.3.4 WeakSet.prototype.has(value)
has: function has(key) {
if (!isObject(key)) return false;
var data = getWeak(key);
if (data === true) return uncaughtFrozenStore(validate(this, NAME)).has(key);
return data && $has(data, this._i);
}
});
return C;
},
def: function (that, key, value) {
var data = getWeak(anObject(key), true);
if (data === true) uncaughtFrozenStore(that).set(key, value);
else data[that._i] = value;
return that;
},
ufstore: uncaughtFrozenStore
};