devela/code/util/paste.rs
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// devela::code::util::paste
//
/// <span class="stab portability" title="re-exported from the `paste` crate">`paste`</span>
/// Allows to paste identifiers together.
///
#[doc = "*Reexported from the [`paste`](https://docs.rs/paste)* crate.\n\n---"]
///
/// Within the `paste!` macro, identifiers inside `[<`...`>]` are pasted
/// together to form a single identifier.
///
/// # Examples
/// ```
/// # use devela::paste;
/// paste! {
/// // Defines a const called `QRST`.
/// const [<Q R S T>]: &str = "success!";
/// }
///
/// fn main() {
/// assert_eq!(
/// paste! { [<Q R S T>].len() },
/// 8,
/// );
/// }
/// ```
///
/// ## Case conversion
///
/// Use `$var:lower` or `$var:upper` in the segment list to convert an
/// interpolated segment to lower- or uppercase as part of the paste. For
/// example, `[<ld_ $reg:lower _expr>]` would paste to `ld_bc_expr` if invoked
/// with `$reg=Bc`.
///
/// Use `$var:snake` to convert CamelCase input to snake\_case.
/// Use `$var:camel` to convert snake\_case to CamelCase. These compose,
/// so for example `$var:snake:upper` would give you SCREAMING\_CASE.
///
/// The precise Unicode conversions are as defined by [`str::to_lowercase`][0]
/// and [`str::to_uppercase`][1].
///
/// [0]: https://doc.rust-lang.org/core/primitive.str.html#method.to_lowercase
/// [1]: https://doc.rust-lang.org/core/primitive.str.html#method.to_uppercase
///
/// ## Pasting documentation strings
///
/// Within the `paste!` macro, arguments to a `#[doc ...]` attribute are
/// implicitly concatenated together to form a coherent documentation string.
///
/// ```
/// # use devela::paste;
/// macro_rules! method_new {
/// ($ret:ident) => {
/// paste! {
/// #[doc = "Create a new `" $ret "` object."]
/// pub fn new() -> $ret { todo!() }
/// }
/// };
/// }
///
/// pub struct Paste {}
///
/// method_new!(Paste); // expands to #[doc = "Create a new `Paste` object"]
/// ```
/// ---
/// ---
#[macro_export]
#[cfg_attr(cargo_primary_package, doc(hidden))]
macro_rules! paste {
($($tt:tt)*) => {
$crate::code::__paste!{ $($tt)* }
}
}
#[doc(inline)]
pub use paste;
#[doc(hidden)] // dont export this
pub use paste_crate::paste as __paste;