#MTTP - My Tiny Toy Parser

What is MTTP?

MTTP is a parser that takes an input like this:

1
2
  21
    211
  22
    221
    222
3

and it gives you this output:

[1,2,[21,[211],22,[221,222]],3]

Why MTTP?

Just for fun and learning. Maybe this little project could help me to write someday a real parser that compiles my own language to Javascript. Maybe it helps someone else.

How can I use MTTP?

git clone https://github.com/pmros/mttp.git
cd mttp
npm install
./bin/mttp < test/input
./bin/mttp --lex_descent < test/input

How does MTTP work?

MTTP tries different implementations of lexers/parsers for the same grammar. Currently there is two implementations:

• Lex/Kappa compiler:

• Lexer: a lexer called lexer.
• Adapter: it just adapts lexer tokens (flex/bison style) to expected Kappa tokens.
• Parser: Kappa, a nice LALR parser.

• Lex/Descent compiler:
  • Lexer: lexer.
  • Adapter: lex (ES6) iterator adapter.
  • Parser: Handwritten recursive descent parser.

Goals

• A parser that it can run at Node.js.
• Indent based syntax.
• Fun to code and easy to read.
• Try different implementations of the same parser.
• Testable.

TODO

• More parser implementations.