README

About
=====
This is a modified version of [asankarc]'s compiler. The tasks performed by each of the files are listed as follows.

 - one.py - A recursive descent parser that can parse the below grammar.
 - two.py - An extension of the one.py's code which transforms
the specified expression list into postfix notation.
 - three.py - A simple stack based machine that can evaluate the postfix notation and execute the postfix notations.
 - four.py - An extension of the two.py's code that generates the three address code representation.
 - five.py - An extension of the four.py's code that performs type checks and does a DAG optimization.

Grammar
=======

- P → D L
- D → B N ; D | B N ;
- B → int | float
- N → N , id | id
- L → S ; L | S ;
- S → id = E | E
- E → E + T | T
- T → T × F | F
- F → ( E ) | num | id

Test Files
=========
The "test" folder contains test files for each compiler (name denotes for which compiler the test is).
Ex:

```
python one.py test/1.txt
```

[asankarc]:https://github.com/asankarc/simple-compiler