node.js - lunr：如何添加新的修剪器

Question

我想在 lunr-language 添加的多语言之前添加一个修剪器（称为改进的修剪器）。我找不到的是如何将现有函数传递给this.pipeline.before()or this.pipeline.after()。这是我总是抛出“错误：找不到现有Fn”的尝试：

fullTextIndex = lunr(function() {

    this.use(lunr.multiLanguage("en", "it"));

    // This works, but put my trimmer at the end of the pipeline
    // this.pipeline.add(improvedTrimmer);

    // This says lunr.trimmer not found. Idem with this.trimmer
    // this.pipeline.after(lunr.trimmer, improvedTrimmer);

    // This seems the most logical choice, but no way (the string is
    // the synthesized trimmer label by the multilanguage plugin
    // this.pipeline.before("lunr-multi-trimmer-en-it", improvedTrimmer);

    // This works, but seems very a dirty workaround
    this.pipeline.after(this.pipeline._stack[0], improvedTrimmer);

在网络上，很少有建议不适用于当前版本的 lunr。