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Tokenizer

Actions Status GitHub license

A simple tokenizer for deno.

Example

import { Tokenizer } from "https://deno.land/x/tokenizer/mod.ts";

const tokenizer = new Tokenizer("abc 123 HELLO [a cool](link)", [
    { type: "HELLO",  pattern: "HELLO" },
    { type: "WORD",   pattern: /[a-zA-Z]+/ },
    { type: "DIGITS", pattern: /\d+/ },
    { type: "LINK", pattern: /\[([^\[]+)\]\(([^\)]+)\)/ },
    { type: "SPACE",  pattern: / /, ignore: true } // Or leave type blank and remove "ignore: true"
]);

// The first option:
console.log(...tokenizer);
// => { type: "WORD", match: "abc", groups: [], position: { start: 0, end: 3 } },
//    { type: "DIGITS", match: "123", groups: [], position: { start: 4, end: 7 } },
//    { type: "HELLO", match: "HELLO", groups: undefined, position: { start: 8, end: 13 } },
//    { type: "LINK", match: "[a](link)", groups: [ "a", "link" ], position: { start: 14, end: 23 } }

// The second option:
// while (!tokenizer.done) {
//     console.log(tokenizer.next().value);
// }
// => { type: "WORD", match: "abc", groups: [], position: { start: 0, end: 3 } },
// => { type: "DIGITS", match: "123", groups: [], position: { start: 4, end: 7 } },
// => { type: "HELLO", match: "HELLO", groups: undefined, position: { start: 8, end: 13 } },
// => { type: "LINK", match: "[a](link)", groups: [ "a", "link" ], position: { start: 14, end: 23 } }

// The third option:
// console.log(tokenizer.tokenize()); // Add a parameter to the tokenize method to override the source string
// => [ { type: "WORD", match: "abc", groups: [], position: { start: 0, end: 3 } },
//      { type: "DIGITS", match: "123", groups: [], position: { start: 4, end: 7 } },
//      { type: "HELLO", match: "HELLO", groups: undefined, position: { start: 8, end: 13 } },
//      { type: "LINK", match: "[a](link)", groups: [ "a", "link" ], position: { start: 14, end: 23 } } ]

TODO

  • Custom patterns using functions
  • Add position information to Token
  • Array patterns (Multiple patterns for the same rule)
  • Documentation
  • Better error handling
  • Group matching
  • Group matching tests
  • Examples
  • More and better tests