bevy/crates/bevy_macro_utils/src/fq_std.rs
Zachary Harrold e5dbde86fb
Moved fq_std from bevy_reflect_derive to bevy_macro_utils (#9956)
# Objective

- Fixes #9363

## Solution

Moved `fq_std` from `bevy_reflect_derive` to `bevy_macro_utils`. This
does make the `FQ*` types public where they were previously private,
which is a change to the public-facing API, but I don't believe a
breaking one. Additionally, I've done a basic QA pass over the
`bevy_macro_utils` crate, adding `deny(unsafe)`, `warn(missing_docs)`,
and documentation where required.
2023-10-02 00:22:57 +00:00

103 lines
2.7 KiB
Rust

//! This module contains unit structs that should be used inside `quote!` and `spanned_quote!`
//! using the variable interpolation syntax in place of their equivalent structs and traits
//! present in `std`.
//!
//! To create hygienic proc macros, all the names must be its fully qualified form. These
//! unit structs help us to not specify the fully qualified name every single time.
//!
//! # Example
//! Instead of writing this:
//! ```ignore
//! quote!(
//! fn get_id() -> Option<i32> {
//! Some(0)
//! }
//! )
//! ```
//! Or this:
//! ```ignore
//! quote!(
//! fn get_id() -> ::core::option::Option<i32> {
//! ::core::option::Option::Some(0)
//! }
//! )
//! ```
//! We should write this:
//! ```ignore
//! use crate::fq_std::FQOption;
//!
//! quote!(
//! fn get_id() -> #FQOption<i32> {
//! #FQOption::Some(0)
//! }
//! )
//! ```
use proc_macro2::TokenStream;
use quote::{quote, ToTokens};
/// Fully Qualified (FQ) short name for [`::core::any::Any`]
pub struct FQAny;
/// Fully Qualified (FQ) short name for [`::std::boxed::Box`]
pub struct FQBox;
/// Fully Qualified (FQ) short name for [`::core::clone::Clone`]
pub struct FQClone;
/// Fully Qualified (FQ) short name for [`::core::default::Default`]
pub struct FQDefault;
/// Fully Qualified (FQ) short name for [`::core::option::Option`]
pub struct FQOption;
/// Fully Qualified (FQ) short name for [`::core::result::Result`]
pub struct FQResult;
/// Fully Qualified (FQ) short name for [`::core::marker::Send`]
pub struct FQSend;
/// Fully Qualified (FQ) short name for [`::core::marker::Sync`]
pub struct FQSync;
impl ToTokens for FQAny {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::any::Any).to_tokens(tokens);
}
}
impl ToTokens for FQBox {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::std::boxed::Box).to_tokens(tokens);
}
}
impl ToTokens for FQClone {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::clone::Clone).to_tokens(tokens);
}
}
impl ToTokens for FQDefault {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::default::Default).to_tokens(tokens);
}
}
impl ToTokens for FQOption {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::option::Option).to_tokens(tokens);
}
}
impl ToTokens for FQResult {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::result::Result).to_tokens(tokens);
}
}
impl ToTokens for FQSend {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::marker::Send).to_tokens(tokens);
}
}
impl ToTokens for FQSync {
fn to_tokens(&self, tokens: &mut TokenStream) {
quote!(::core::marker::Sync).to_tokens(tokens);
}
}