Awesome
Tokenizer
A simple Deno library
<div align = center> </div>
<br>
Examples
import { Tokenizer } from 'https://deno.land/x/tokenizer/mod.ts';
const input = 'abc 123 HELLO [a cool](link)';
const rules = [{
type : 'HELLO' ,
pattern : 'HELLO'
},{
type : 'WORD' ,
pattern : /[a-zA-Z]+/
},{
type : 'DIGITS' ,
pattern : /\d+/ ,
value : m => Number.parseInt(m.match)
},{
type : 'LINK' ,
pattern : /\[([^\[]+)\]\(([^\)]+)\)/
},{
type : 'SPACE' ,
pattern : / / ,
ignore: true // Or leave type blank and remove "ignore: true"
}];
const tokenizer = new Tokenizer(input,rules);
<br>
Option A
console.log(...tokenizer);
{ type: "WORD", match: "abc", value: "abc", groups: [], position: { start: 0, end: 3 } },
{ type: "DIGITS", match: "123", value: 123, groups: [], position: { start: 4, end: 7 } },
{ type: "HELLO", match: "HELLO", value: "HELLO", groups: [], position: { start: 8, end: 13 } },
{ type: "LINK", match: "[a cool](link)", value: "[a cool](link)", groups: [ "a cool", "link" ], position: { start: 14, end: 28 } }
<br>
Option B
while(!tokenizer.done)
console.log(tokenizer.next().value);
{ type: "WORD", match: "abc", value: "abc", groups: [], position: { start: 0, end: 3 } }
{ type: "DIGITS", match: "123", value: 123, groups: [], position: { start: 4, end: 7 } }
{ type: "HELLO", match: "HELLO", value: "HELLO", groups: [], position: { start: 8, end: 13 } }
{ type: "LINK", match: "[a cool](link)", value: "[a cool](link)", groups: [ "a cool", "link" ], position: { start: 14, end: 28 } }
<br>
Option C
// Add a parameter to the tokenize method to override the source string
console.log(tokenizer.tokenize());
[{ type: "WORD", match: "abc", value: "abc", groups: [], position: { start: 0, end: 3 } },
{ type: "DIGITS", match: "123", value: 123, groups: [], position: { start: 4, end: 7 } },
{ type: "HELLO", match: "HELLO", value: "HELLO", groups: [], position: { start: 8, end: 13 } },
{ type: "LINK", match: "[a cool](link)", value: "[a cool](link)", groups: [ "a cool", "link" ], position: { start: 14, end: 28 } } ]
TODO
- Custom patterns using functions
- Add position information to Token
- Array patterns (Multiple patterns for the same rule)
- Documentation
- Better error handling
- Group matching
- Value transform
- More and better tests for everything
- Examples
- Line and column information? Or just a helper function to get line and column from index
- BNF / EBNF ?
- Generate a tokenizer