Viper Programming Language

WIP - It's like Python, but faster.

Viper is a simple, Python-like programming language that compiles to x86-64 assembly. It features a clean syntax and efficient compilation to native code.

Features

Core Language Features

• Variables and Assignment: x = 5
• Arithmetic Operations: +, -, *, /
• Print Statements: print(expression)

Control Flow

• Conditional Statements: if (condition) { ... } else { ... }
• While Loops: while (condition) { ... }
• For Loops: for (variable in range(n)) { ... }
• Loop Control: break, continue (planned)

Comparison Operators

• Equality: ==, !=
• Relational: <, >, <=, >=

Built-in Functions

• range(n): Generate numbers from 0 to n-1 (for use in for loops)
• print(expr): Output the value of an expression

Syntax Examples

Basic Operations

# Variables and arithmetic
x = 10
y = 5
sum = x + y
print(sum)  # Outputs: 15

Conditional Statements

if (x > y) {
    print(1)  # x is greater
} else {
    print(0)  # y is greater or equal
}

Loops

# While loop
counter = 0
while (counter < 5) {
    print(counter)
    counter = counter + 1
}

# For loop
for (i in range(5)) {
    print(i)  # Prints 0, 1, 2, 3, 4
}

Calculator Example

The calculator.vp file demonstrates various Viper features:

# Factorial calculation
fact = 1
for (i in range(6)) {
    if (i > 1) {
        fact = fact * i
    }
}
print(fact)  # Outputs: 120 (5!)

# Power calculation
base = 2
exponent = 3
power = 1
for (i in range(exponent)) {
    power = power * base
}
print(power)  # Outputs: 8 (2^3)

# Sum of numbers 1 to 10
total = 0
for (i in range(11)) {
    if (i > 0) {
        total = total + i
    }
}
print(total)  # Outputs: 55

Building and Running

1. Build the compiler:

   cargo build --release

2. Compile a Viper program:

   ./target/release/viper example.vp

3. Assemble and link (Linux x86-64):

   nasm -f elf64 output.asm -o output.o
   ld output.o -o program
   ./program

Language Grammar

program         → statement*
statement       → assignment | print_stmt | if_stmt | while_stmt | for_stmt | break_stmt | continue_stmt
assignment      → IDENTIFIER "=" expression
print_stmt      → "print" "(" expression ")"
if_stmt         → "if" "(" comparison ")" "{" statement* "}" ("else" "{" statement* "}")?
while_stmt      → "while" "(" comparison ")" "{" statement* "}"
for_stmt        → "for" "(" IDENTIFIER "in" expression ")" "{" statement* "}"
break_stmt      → "break"
continue_stmt   → "continue"
comparison      → expression (("==" | "!=" | "<" | ">" | "<=" | ">=") expression)?
expression      → term (("+"|"-"|"*"|"/") term)*
term            → NUMBER | IDENTIFIER | "(" expression ")" | function_call
function_call   → IDENTIFIER "(" expression ")"

TODO

Language Features

• Implement break and continue statements properly
• Add support for floating-point arithmetic
• Function definitions and calls
• Arrays and string support
• More built-in functions

Compiler Improvements

• Implement arbitrary precision arithmetic
• Multi-Platform Support - Add support for macOS (Mach-O)
• Cross-compilation support
• Better error reporting and debugging
• Keep compiler frontend decoupled from backend-specific details
• Optimize generated assembly code

Development Tools

• Syntax highlighting
• REPL (Read-Eval-Print Loop)
• Standard library
• Package manager

Contributing

Viper is a work in progress. Contributions are welcome! Please feel free to submit issues and pull requests.

License

This project is open source and available under the MIT License.