Elm Calculator 🧮

This project was developed as a university assignment to explore Domain-Specific Languages (DSLs) by creating a parser in Elm for mathematical equations. Unlike JavaScript, Elm doesn't provide direct string-to-calculation conversion, making this an intriguing challenge.

• Interactive UI with clickable buttons and displays
• Input and output displays

• Basic operations: Addition, Subtraction, Multiplication, Division
• Negation support
• Multiple number base input support:
  • Hexadecimal (e.g., 0xA+5)
  • Octal (e.g., 0o10+2)
  • Binary (e.g., 0b101+3)
  • Decimal (standard input)

• Prevents impossible states
• Handles division by zero
• Displays error messages for invalid operations

• Parentheses and grouping support: ( ), [ ], { }
• Respects mathematical precedence of different grouping symbols
• Outputs always in decimal

• Keyboard input recommended for special characters
• Allowed characters: 0-9, +-*/, enter, c, backspace
• Special character input (x, o, b, A-F) via keyboard only

Design based on the iOS calculator app. All credit to their design team.

elm-test

Compiling > Starting tests

elm-test 0.19.1-revision12
--------------------------

Running 24 tests. To reproduce these results, run: elm-test --fuzz 100 --seed 38497853693389

TEST RUN PASSED

Duration: 176 ms
Passed:   24
Failed:   0

Compile Elm code to JavaScript first

elm make src/Main.elm --output=calc.js

Launch development environment

elm reactor

Then navigate to: http://localhost:8000/index.html

• AI-generated tests supplemented manual testing to make sure each possibility is correctly parsed.