BASIC DSL for Rust 🦀

A Rust procedural macro crate that provides a BASIC interpreter embedded as a domain-specific language with direct token parsing for excellent IDE support.

Features

Variables: Assignment with LET and arithmetic expressions
Input/Output: INPUT for reading user input and PRINT statements with flexible formatting
Control Flow: IF...THEN GOTO conditionals and GOTO jumps
Loops: FOR...NEXT loops with optional STEP increment
Program Structure: Line numbers, labels, and END termination
IDE Support: Full syntax highlighting, error reporting, and code completion

Usage

Add this to your Cargo.toml:

[dependencies]
basic-dsl = "0.2.0"

Then use the macro in your Rust code:

use basic_dsl::basic;

fn main() {
    basic! {
        10 LET X = 1
        20 PRINT X
        30 IF X < 5 THEN GOTO 50
        40 PRINT "DONE"
        45 END
        50 LET X = X + 1
        60 GOTO 20
    }
}

Syntax

The DSL supports classic BASIC syntax with modern IDE integration:

Statements

LET variable = expression - Variable assignment
PRINT [expression, ...] - Output values or strings (comma creates tab stops for columnar formatting, semicolon concatenates, or empty for newline)
INPUT [prompt,] variable - Read user input from stdin into variable (auto-detects numbers vs strings)
GOTO label - Jump to line number
IF condition THEN GOTO label - Conditional jump
FOR variable = start TO end [STEP increment] - Loop initialization
NEXT [variable] - Loop increment and condition check
END - Terminate program

Expressions

Arithmetic: +, -, *, / with proper precedence
Comparisons: <, <=, =, >=, >
Literals: Numbers (42) and strings ("Hello")
Variables: Any valid identifier (X, COUNTER, etc.)
Parentheses: For grouping expressions

Program Structure

Line numbers act as labels for jumps and program flow
Statements are written directly without quotes for full IDE support
Nested FOR loops and complex expressions are fully supported

Examples

Enhanced PRINT Statement

basic! {
    10 PRINT "Name", "Age", "Score"    // Tab-separated columns
    20 PRINT "Alice", 25, 95           // Comma creates tab stops  
    30 PRINT "Bob", 30, 87             // For columnar output
    40 PRINT "Concat:"; "A"; "B"       // Semicolon concatenates
    50 PRINT                           // Empty PRINT = newline
    60 END
}

Interactive INPUT

basic! {
    10 PRINT "Number Guessing Game"
    20 INPUT "Enter your guess", GUESS
    30 IF GUESS = 42 THEN GOTO 60
    40 PRINT "Wrong! The answer was 42"
    50 GOTO 70
    60 PRINT "Correct! You got it!"
    70 END
}

RustBasic FizzBuzz

basic! {
    10 PRINT "RustBasic FizzBuzz from 1 to 20:"
    20 FOR I = 1 TO 20
    30 LET A = I / 3 * 3
    40 LET B = I / 5 * 5
    50 IF A = I THEN GOTO 100
    60 IF B = I THEN GOTO 170
    70 PRINT I
    80 GOTO 180
    100 IF B = I THEN GOTO 150
    110 PRINT "Rust"
    120 GOTO 180
    150 PRINT "RustBasic"
    160 GOTO 180
    170 PRINT "Basic"
    180 NEXT I
    190 END
}

Running Examples

This repository includes example programs that you can run:

# Run the RustBasic FitzBuzz example
cargo run --bin basic

# Run comprehensive feature tests  
cargo run --bin test-features

# Run enhanced PRINT statement demo
cargo run --bin print-demo

# Test INPUT functionality with various scenarios
cargo run --bin input-test

# Play the interactive number guessing game
cargo run --bin number-guessing-game

License

Licensed under the European Union Public Licence 1.2 (EUPL-1.2).

basic-dsl 0.3.0