Formal Languages and Compilers Project: Kotlin Interpreter (in Python)

An Interpreter of Kotlin language is defined by:

1. A lexer that turns a sequence of characters (source program) into a sequence of tokens
2. A parser that takes the previous sequence of tokens and produces an abstract syntax tree (AST)
3. An interpreter (evaluator) that traverses the AST and executes the code line by line

---

Tutorial

Via PyCharm:

1. Execute main.py
2. Insert a number indicating the test case you want to interpret (from 0 to 6)

Via Terminal (write the following commands):

1. cd path-to-project-directory
2. python main.py
3. Insert a number indicating the test case you want to interpret (from 0 to 6)

N.B.: Test cases 3, 4 and 5 present errors

How to create your own executable from console:

• Linux/MacOS:

pip install pyinstaller

pyinstaller --onefile --hidden-import=Interpreter --hidden-import=Parser --hidden-import=Lexer --add-data "Tests/*:Tests" -n Interpreter main.py

• Windows:

pip install pyinstaller

pyinstaller --onefile --hidden-import=Interpreter --hidden-import=Parser --hidden-import=Lexer --add-data "Tests/*;Tests" -n Interpreter main.py

---

Restriction of Kotlin’s grammar used

Kotlin grammar: https://kotlinlang.org/docs/reference/grammar.html

DATA TYPES

1. Boolean
2. Integer
3. String

ARITHMETIC OPERATORS

1. Addition (+)
2. Subtraction (-)
3. Multiplication (*)
4. Division (/)

LOGICAL OPERATORS

1. Logical and (&&)
2. Logical or (||)
3. Logical not (!)

COMPARISON OPERATORS

1. Equal to (==)
2. Not equal (!=)
3. Greater than (>)
4. Less than (<)
5. Greater than or equal to (>=)
6. Less than or equal to (<=)

BRANCHING INSTRUCTION

1. if (...) {...} else {...}

LOOP INSTRUCTION

1. while (...) {...}
2. for (i in ...) {...}

I/O INSTRUCTION

1. println(...) (O)
2. readLine(...) (I)

OTHER LANGUAGE FEATURES

1. Functions
2. Comments and Whitespaces (ignored during execution)

---

Libraries

PLY (Python Lex-Yacc): https://ply.readthedocs.io/en/latest/

Simple Colors: https://pypi.org/project/simple-colors/

PyInstaller: https://pyinstaller.org/en/stable/

---

Students:

• Fioretti Maria Lucia (590016, m.fioretti1@studenti.poliba.it)

• Preziosa Alessia (590012, a.preziosa2@studenti.poliba.it)