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| // Harry Kruger | |
| // License: MIT | |
| class LimitedSet extends Set { | |
| constructor(limit = 0, maxAge = 0, sweepInterval = 1000 * 60, init) { | |
| super(init); | |
| this.limit = limit; | |
| this.maxAge = maxAge; | |
| this._sweepInterval = sweepInterval; | |
| this._creationDates = new Map(); | |
| if (this.maxAge && this.sweepInterval) this._createInterval(this.sweepInterval); | |
| } | |
| set sweepInterval(val) { | |
| this._updateInterval(val); | |
| this._sweepInterval = val; | |
| } | |
| get sweepInterval() { | |
| return this._sweepInterval; | |
| } | |
| _createInterval(sweepInterval) { | |
| this.interval = setInterval(this._sweep.bind(this), sweepInterval); | |
| } | |
| _updateInterval(sweepInterval) { | |
| if (this.interval) { | |
| this._clearInterval(this.interval); | |
| this._createInterval(sweepInterval); | |
| } | |
| } | |
| _clearInterval(interval) { | |
| clearInterval(interval); | |
| } | |
| _sweep() { | |
| for (let value of this.values()) { | |
| // check if date is older then maxAge | |
| if (this._creationDates.get(value) + this.maxAge < Date.now()) this.delete(value); | |
| } | |
| } | |
| add(value) { | |
| // ensure correct limit | |
| if (this.size && this.limit && this.size >= this.limit) this.delete(this.values().next().value); | |
| this._creationDates.set(value, Date.now()); | |
| super.add(value); | |
| } | |
| delete(value) { | |
| this._creationDates.delete(value); | |
| super.delete(value); | |
| } | |
| destroy() { | |
| this._clearInterval(this.interval); | |
| } | |
| } | |
| module.exports = LimitedSet; |
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