SLAC is a small and simple compiler which converts a single expression statement into an AST.
It is written in Rust and as such compiles easily as an executable, wasm module, or standalone DLL.
```rust use slac::{ast::Expression, compile};
fn main() { let ast = compile("1 * 2 + 3");
let expected = Expression::Binary {
left: Box::new(Expression::Binary {
left: Box::new(Expression::Literal(Value::Number(1.0))),
right: Box::new(Expression::Literal(Value::Number(2.0))),
operator: Token::Star,
}),
right: Box::new(Expression::Literal(Value::Number(3.0))),
operator: Token::Plus,
};
assert_eq!(result, Ok(expected));
} ```
SLAC features a built-in tree walk interpreter.
Create an Environment which houses the variables and user defined functions. Then use the TreeWalkingInterpreter class to execute the AST against the environment.
```rust use slac::compile; use slac::environment::Environment; use slac::interpreter::TreeWalkingInterpreter; use slac::value::Value;
fn main() { let ast = compile("somevar > 5").unwrap(); let mut env = Environment::default(); env.addvar("some_var", Value::Number(42.0));
let result = TreeWalkingInterpreter::interprete(&env, &ast);
assert_eq!(result, Value::Boolean(true));
} ```
The script syntax itself is similar to Delphi Pascal code.
```pascal // arithmetic operators 40 + 1 * 2 // > 42
// Integer Division and Modulo 50 div 20 mod 2 // > 2
// comparisons 50 + 50 = 100 // > True
// logical operators True and not False // > True
// grouping (40 + 1) * 2 // > 82
// arrays [1, 2, 3] + ['Four'] // > [1, 2, 3, 'Four']
// application defined external functions someFunc(true) // > depends on the definition of 'someFunc'
// application defined variables SOMEVAR + -10 // > depends on the definition of 'SOMEVAR'
```
The minimum required Rust toolchain version for SLAC is 1.70.0 or higher.
Use cargo add slac to install the library from crates.io as a dependency in your application.
Copyright 2023 Dennis Prediger
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
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