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//! Convenience macros to work with the `Option` type.
//!
//! Use `val!` and `rval!`, if you expect `Option` to contain an value.
//! The macro will fail with a [ToqlError::NoneError](crate::error::ToqlError::NoneError), if `Option` is `None`.
//!
//! ### Example
//! With a field like `name: Option<String>` in an object `user` you can write
//! ```rust, ignore
//! use toql_core::{rval, val};
//! use toql_derive::Toql;
//!
//! #[derive(Toql)]
//! struct User {
//!     #[toql(key)]
//!     id: u64,
//!     name: Option<String> // Selectable field
//! }
//!
//! let user = User{ id: 5, name: Some("Peter".to_string())};
//!
//! let name : &String = rval!(user.name).expect("Name is None.");
//! let name : String = val!(user.name).expect("Name is None.");
//! ```
//!
//! The macros are useful, because typical Toql derive structs contain a lot of
//! selectable fields, which are optional. The macros make it more convenenient to
//! get the values out of those fields.
#[macro_export]
macro_rules! val {
    ($x: expr) => {
        $x.ok_or(toql::none_error!())?
    };
}
#[macro_export]
macro_rules! rval {
    ($x: expr) => {
        $x.as_ref().ok_or(toql::none_error!())?
    };
}