overpass-frontend/src/EvaluatorOperator.js

A JavaScript (NodeJS/Browser) library to easily access data from OpenStreetMap via Overpass API or from an OSM File. The objects can directly be used with LeafletJS or exported to GeoJSON. Data will be cached in the browser memory.

const evaluatorExport = require('./evaluatorExport')
const EvaluatorPart = require('./EvaluatorPart')
const EvaluatorValue = require('./EvaluatorValue')

module.exports = class EvaluatorOperator extends EvaluatorPart {
  constructor (op, left, right) {
    super()
    this.op = op
    this.left = left
    this.right = right
  }

  toJSON () {
    return { op: this.op, left: evaluatorExport(this.left), right: evaluatorExport(this.right) }
  }

  toValue () {
    if (this.left.toValue() === null || this.right.toValue() === null) {
      return null
    }
    return this.eval({})
  }

  simplify () {
    const v = this.toValue()
    if (v !== null) {
      return new EvaluatorValue(v)
    }
    const left = this.left ? this.left.simplify() : null
    const right = this.right ? this.right.simplify() : null
    return new this.constructor(this.op, left, right)
  }

  compileLokiJS () {
    return { needMatch: true }
  }

  calcRequestProperties () {
    let result = this.requestProperties
    if (this.left) {
      result |= this.left.calcRequestProperties()
    }
    if (this.right) {
      result |= this.right.calcRequestProperties()
    }
    return result
  }
}