23nd October
Finishing the parser
The parser is complete :). All there was left to do was to remove the todo's from
the parseLetStatement & parseReturnStatement method. As at the time of parsing
let & return statements there was no support for expressions.
The repl was updated to now return the parsed output of the program. So as is,
it returns the ast for the monkey programming language, which I feel is awesome.
You can see glimplses of how tree-sitter (opens in a new tab) could work.
The amount of learning so far has been amazing and I understand what the terms expressions &
statements mean. Also, realized that I've been using those two terms incorrectly.
These are some of the output of the code:
Let statements
Welcome to monkey v0.0.0
Press ctrl-d to exit.
>> let x = 1;
let x = 1;
>> let y = 1 * 2 * 3 * 4 * 5
let y = ((((1 * 2) * 3) * 4) * 5);
>> let z = 2 / 3 + 1 - 1
let z = (((2 / 3) + 1) - 1);
>>
Function Literal & Calls
>> fn() { return fn(x, y) { return x + y }}
fn()return fn(x, y)return (x + y);; // for some reason it's printing two ';', will fix it later
>>Errors
>> let a + b * 3
__,__
.--. .-" "-. .--.
/ .. \/ .-. .-. \/ .. \
| | '| / Y \ |' | |
| \ \ \ 0 | 0 / / / |
\ '- ,\.-"""""""-./, -' /
''-' /_ ^ ^ _\ '-''
| \._ _./ |
\ \ '~' / /
'._ '-=-' _.'
'-----'
Parser errors:
expected next token to be =, got +
no prefix parse function for +
>>