include_tt 1.1.0

Macros for ultra-flexible injection of compiler trees, literals, or binary data into Rust syntax trees from external sources.
Documentation 
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use alloc::vec::Vec;
use core::slice::IterMut;
use proc_macro2::{Group, TokenStream as TokenStream2, TokenTree as TokenTree2};

/*
	TODO, At the moment this is not optimally done :(.
*/

/// A small function that provides the ability
/// to iterate and replace trees in place.
pub fn replace_tree_in_group<R>(
	real_group: &mut Group,

	next: impl FnOnce(IterMut<'_, TokenTree2>) -> R,
) -> R {
	let span = real_group.span();
	let delimeter = real_group.delimiter();

	let mut allts: Vec<TokenTree2> = real_group.stream().into_iter().collect();
	let result = next(allts.iter_mut());

	let mut ngroup = Group::new(delimeter, TokenStream2::from_iter(allts));
	ngroup.set_span(span);
	*real_group = ngroup;

	result
}

/// A small function that provides the ability
/// to iterate and replace trees in place.
///
/// For a group, use the `replace_tree_in_group` function.
pub fn replace_tree_in_stream<R>(
	stream: &mut TokenStream2,

	next: impl FnOnce(IterMut<'_, TokenTree2>) -> R,
) -> R {
	let mut allts: Vec<TokenTree2> = core::mem::take(stream).into_iter().collect();

	let result = next(allts.iter_mut());

	*stream = TokenStream2::from_iter(allts);
	result
}