use rhai::{Engine, EvalAltResult, ParseErrorType, RegisterFn, INT}; #[test] fn test_tokens_disabled() { let mut engine = Engine::new(); engine.disable_symbol("if"); // disable the 'if' keyword assert!(matches!( *engine.compile("let x = if true { 42 } else { 0 };").expect_err("should error").0, ParseErrorType::MissingToken(ref token, _) if token == ";" )); engine.disable_symbol("+="); // disable the '+=' operator assert!(matches!( *engine.compile("let x = 40 + 2; x += 1;").expect_err("should error").0, ParseErrorType::BadInput(ref s) if s == "Unexpected '+='" )); } #[test] fn test_tokens_custom_operator() -> Result<(), Box> { let mut engine = Engine::new(); // Register a custom operator called `foo` and give it // a precedence of 160 (i.e. between +|- and *|/). engine.register_custom_operator("foo", 160).unwrap(); // Register a binary function named `foo` engine.register_fn("foo", |x: INT, y: INT| (x * y) - (x + y)); assert_eq!( engine.eval_expression::("1 + 2 * 3 foo 4 - 5 / 6")?, 15 ); assert_eq!( engine.eval::( r" fn foo(x, y) { y - x } 1 + 2 * 3 foo 4 - 5 / 6 " )?, -1 ); Ok(()) }