trie-parser.js

   1
   2 var Parser = require("./parser");
   3
   4 module.exports = makeParserFromTrie;
   5 function makeParserFromTrie(trie, makeProducer, callback, fallback) {
   6     var children = {};
   7     var characters = Object.keys(trie.children);
   8     characters.forEach(function (character) {
   9         children[character] = makeParserFromTrie(
  10             trie.children[character],
  11             makeProducer,
  12             callback,
  13             fallback
  14         );
  15     });
  16     var producer;
  17     if (trie.value) {
  18         producer = makeProducer(trie.value);
  19     }
  20     return characters.reduceRight(function (next, expected) {
  21         return function (state) {
  22             return function (character) {
  23                 if (character === expected) {
  24                     return callback(children[character](state));
  25                 } else {
  26                     return next(state)(character);
  27                 }
  28             };
  29         };
  30     }, function (state) {
  31         if (producer) {
  32             return callback(producer(state));
  33         } else {
  34             return fallback(state);
  35         }
  36     });
  37 }
  38