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@polkadot/util

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.objectProperty = objectProperty; exports.objectProperties = objectProperties; /** * @name objectProperty * @summary Assign a get property on the input object */ function objectProperty(that, key, getter, getName, index = 0) { const name = getName ? getName(key, index) : key; // There are 3 approaches here - // - Object.prototype.hasOwnProperty.call(that, key) - this only checks the current class, i.e // will retuirn false if the property is set in the parent class // - isUndefined(...) - this may yield a false positive when the property is there, but not set. // Additionally, on pre-defined getters it may make a call // - key in that - Does not need to be combined with either of the above and checks the full chain if (!(name in that)) { Object.defineProperty(that, name, { enumerable: true, // Unlike in lazy, we always call into the upper function, i.e. this method // does not cache old values (it is expected to be used for dynamic values) get: function () { return getter(key, index, this); } }); } } /** * @name objectProperties * @summary Assign get properties on the input object */ function objectProperties(that, keys, getter, getName) { for (let i = 0, count = keys.length; i < count; i++) { objectProperty(that, keys[i], getter, getName, i); } }