mitoy

Toy interpreted programming language

A little language written in my spare time with python and rply. It's nothing special or serious, but I decided to share anyway. I received some nice experience that can help me in future projects (maybe one day I will create worthy programming language).

You can find language's grammar in this file. Example programs and their test you can find in this folder.

Example program

import t "testing"

fn Fact(n) {
    if n < 1 { ret 1 };
    ret n * Fact(n - 1);
}

# Function will be called when testing
fn Test() {
    t.Describe("Factorial function", fn (Case) {
        Case("!0 should be equal to 1", fn (Test) {
            Test(Fact(0)).ToBeEqual(1);
        });

        Case("Fact should return correct values", fn (Test) {
            Test(Fact(4)).ToBeEqual(24);
            Test(Fact(5)).ToBeEqual(120);
        });
    });
}

# Function will be called when calling file directly
fn Main() {
    TraceNl(Fact(4));  # Outputs 24
    TraceNl(Fact(5));  # Outputs 120
}

Built-In methods

From file mitoy/std.py

• Str(val) turn val into string

• Int(val) turn val into int (or throw an exception)

• Float(val) turn val into float (or throw an exception)

• StrSlice(val, s, e) return part of val string from index s to e

• StrLen(val) return length of string val

• Input(val) ask the user for input and return inputted line

• WriteToFile(filename, content) write content into a file with filename

• TraceNl(val) print val with a newline at the end of line

• Trace(val) print val without a newline at the end of line

Running

python3 -m pip install -r requirements.txt

python3 mitoy 'path/to/program.mitoy' # run application
python3 mitoy --test 'path/to/folder' # run tests for every file in folder

Notes

• This project probably won't be developed further