Struct arithmetic_eval::fns::Dbg

pub struct Dbg;

Available on crate feature std only.

Acts similarly to the dbg! macro, outputting the argument(s) to stderr and returning them. If a single argument is provided, it’s returned as-is; otherwise, the arguments are wrapped into a tuple.

Examples

let program = "dbg(1 + 2) > 2.5";
let program = Untyped::<F32Grammar>::parse_statements(program)?;
let module = ExecutableModule::new("test_dbg", &program)?;

let mut env = Environment::new();
env.insert_native_fn("dbg", fns::Dbg);
let value = module.with_env(&env)?.run()?;
// Should output `[test_assert:1:5] 1 + 2 = 3` to stderr.
assert_eq!(value, Value::Bool(true));

Trait Implementations

impl Clone for Dbg

fn clone(&self) -> Dbg

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Dbg

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Dbg

fn default() -> Dbg

Returns the “default value” for a type.

impl<T: Display> NativeFn<T> for Dbg

fn evaluate( &self, args: Vec<SpannedValue<T>>, ctx: &mut CallContext<'_, T> ) -> EvalResult<T>

Executes the function on the specified arguments.

impl Copy for Dbg