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'use strict';
var d = require('d')
, create = Object.create, defineProperties = Object.defineProperties
, generateName, Symbol;
generateName = (function () {
var created = create(null);
return function (desc) {
var postfix = 0;
while (created[desc + (postfix || '')]) ++postfix;
desc += (postfix || '');
created[desc] = true;
return '@@' + desc;
};
}());
module.exports = Symbol = function (description) {
var symbol;
if (this instanceof Symbol) {
throw new TypeError('TypeError: Symbol is not a constructor');
}
symbol = create(Symbol.prototype);
description = (description === undefined ? '' : String(description));
return defineProperties(symbol, {
__description__: d('', description),
__name__: d('', generateName(description))
});
};
Object.defineProperties(Symbol, {
create: d('', Symbol('create')),
hasInstance: d('', Symbol('hasInstance')),
isConcatSpreadable: d('', Symbol('isConcatSpreadable')),
isRegExp: d('', Symbol('isRegExp')),
iterator: d('', Symbol('iterator')),
toPrimitive: d('', Symbol('toPrimitive')),
toStringTag: d('', Symbol('toStringTag')),
unscopables: d('', Symbol('unscopables'))
});
defineProperties(Symbol.prototype, {
properToString: d(function () {
return 'Symbol (' + this.__description__ + ')';
}),
toString: d('', function () { return this.__name__; })
});
Object.defineProperty(Symbol.prototype, Symbol.toPrimitive, d('',
function (hint) {
throw new TypeError("Conversion of symbol objects is not allowed");
}));
Object.defineProperty(Symbol.prototype, Symbol.toStringTag, d('c', 'Symbol'));
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