pLox

pLox is a Python implementation of the language Lox based on the book from Robert Nystrom's Crafting Interpreters.

The book implements the language in Java (Part 1) and C (Part 2). pLox is a Python 'translation' of the Java code from Part 1. Just for fun and to learn some Python :-).

For more details, see: The Lox Language

Interpreter

Running pLox without arguments will yield a REPL.

python -m lox

REPL:

> print "Hello, World!";
Hello, World!
>

Executing a file can be done by passing a file as argument.

> python -m lox myfile.plox

Examples

String variable

> var foo = "foo";
> print foo;
foo

Simple addition

> print 42 + 1337;
1379

Simple for-loop

> for (var i = 0; i < 10; i = i + 1) { print i; }
0
1
.
9

Recursive Fibonacci function

> fun fib(n) { if (n < 2) { return n; } return fib(n - 1) + fib(n - 2); }
> print fib(15);
610

Class

> class Point { init(x, y) { this.x = x; this.y = y; } }
> var point = Point(10, 12);
> print point.x;
10
> print point.y;
12

Inheritance

> class Foo { spam() { print "foo"; } }
> class Bar < Foo { spam() { super.spam(); print "bar"; } }
> var bar = Bar();
> bar.spam();
foo
bar