Method extend

external/.scrollLibs.js:16971–16991

(particleOrStr)

  // todo: should take a parsers? to decide whether to overwrite or append.
  // todo: this is slow.
  extend(particleOrStr) {
    const particle = particleOrStr instanceof Particle ? particleOrStr : new Particle(particleOrStr)
    const usedCues = new Set()
    particle.forEach(sourceParticle => {
      const cue = sourceParticle.cue
      let targetParticle
      const isAnArrayNotMap = usedCues.has(cue)
      if (!this.has(cue)) {
        usedCues.add(cue)
        this.appendLineAndSubparticles(sourceParticle.getLine(), sourceParticle.subparticlesToString())
        return true
      }
      if (isAnArrayNotMap) targetParticle = this.appendLine(sourceParticle.getLine())
      else {
        targetParticle = this.touchParticle(cue).setContent(sourceParticle.content)
        usedCues.add(cue)
      }
      if (sourceParticle.length) targetParticle.extend(sourceParticle)
    })
    return this
  }
  lastParticle() {
    return this.getSubparticles()[this.length - 1]
  }