rspect - A Scheme Interpreter in Rust

This is a simple Scheme interpreter written in Rust.

Building

To build the interpreter, you need to have Rust and Cargo installed. Navigate to the project directory in your terminal and run:

cargo build --release

Running

To run the interpreter's REPL (Read-Eval-Print Loop), use:

cargo run

This will start an interactive session where you can type Scheme expressions.

To exit the REPL, press Ctrl+C, Ctrl+D, or type exit and press Enter.

Supported Syntax

The interpreter currently supports a subset of Scheme, including:

• Core Forms:
  • define: Define variables and functions.
  • if: Conditional execution.
  • lambda: Create anonymous functions. Example: ((lambda (x) (* x x)) 5) ; Output: 25
  • quote / ': Prevent evaluation. Example: '(+ 1 2) ; Output: (+ 1 2)
• Macros (from stdlib.scm):
  • case: Selects a clause based on matching a key. Example: (case (* 2 3) ((1 5 7) "odd") ((2 4 6) "even")) ; Output: "even"
  • let: Bind variables locally. Example: (let ((x 1) (y 2)) (+ x y)) ; Output: 3
  • let*: Sequential local binding. Example: (let* ((x 1) (y (+ x 1))) (* x y)) ; Output: 2
  • letrec: Recursive local binding (for functions). Example: (letrec ((fact (lambda (n) (if (zero? n) 1 (* n (fact (- n 1))))))) (fact 5)) ; Output: 120