lsp-max-ast 26.7.3

/// Calls a method on the first node that matches any of the provided types.
/// Returns the result of the method call.
///
/// # Example
///
/// ```rust, ignore
/// use ast::generated::{FunctionDefinition, ClassDefinition};
/// use lsp_max_ast::dispatch_once;
///
/// /* ... */
/// let result = dispatch_once!(node.lower(), [
///     FunctionDefinition => return_something(db, param),
///     ClassDefinition => return_something(db, param)
/// ]);
/// ```
#[macro_export]
macro_rules! dispatch_once {
    ($node:expr, [$($ty:ty => $method:ident($($param:expr),*)),*]) => {
        {
            let _node = &$node;
            if false {
                unreachable!()
            }
            $(
                else if let Some(n) = _node.downcast_ref::<$ty>() {
                    Some(n.$method($($param),*))
                }
            )*
            else {
                None
            }
        }
    };
}

/// Calls a method on any node that matches any of the provided types.
/// Unlike dispatch_once, it will not return.
///
/// # Example
///
/// ```rust, ignore
/// use ast::generated::{FunctionDefinition, ClassDefinition};
/// use lsp_max_ast::dispatch;
///
/// /* ... */
/// dispatch!(node.lower(), [
///     FunctionDefinition => get_something(db, param),
///     ClassDefinition => get_something(db, param)
/// ]);
/// ```
#[macro_export]
macro_rules! dispatch {
    ($node:expr, [$($ty:ty => $method:ident($($param:expr),*)),*]) => {
        {
            let _node = &$node;
            $(
                if let Some(n) = _node.downcast_ref::<$ty>() {
                    n.$method($($param),*)?;
                };
            )*
        }
    };
}