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SubjectRe: [PATCH] rust: macros: update 'paste!' macro to accept string literals
On Sun,  8 Oct 2023 05:48:18 -0400
Trevor Gross <tmgross@umich.edu> wrote:

> Enable combining identifiers with string literals in the 'paste!' macro.
> This allows combining user-specified strings with affixes to create
> namespaced identifiers.
>
> This sample code:
>
> macro_rules! m {
> ($name:lit) => {
> paste!(struct [<_some_ $name _struct_>];)
> }
> }
>
> m!("foo_bar");
>
> Would previously cause a compilation error. It will now generate:
>
> struct _some_foo_bar_struct_;
>
> Reported-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
> Signed-off-by: Trevor Gross <tmgross@umich.edu>

Reviewed-by: Gary Guo <gary@garyguo.net>

> ---
>
> Original mention of this problem in [1]
>
> [1]: https://lore.kernel.org/rust-for-linux/20231008.164906.1151622782836568538.fujita.tomonori@gmail.com/
>
> rust/macros/paste.rs | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/rust/macros/paste.rs b/rust/macros/paste.rs
> index 385a78434224..f40d42b35b58 100644
> --- a/rust/macros/paste.rs
> +++ b/rust/macros/paste.rs
> @@ -9,7 +9,15 @@ fn concat(tokens: &[TokenTree], group_span: Span) -> TokenTree {
> loop {
> match tokens.next() {
> None => break,
> - Some(TokenTree::Literal(lit)) => segments.push((lit.to_string(), lit.span())),
> + Some(TokenTree::Literal(lit)) => {
> + // Allow us to concat string literals by stripping quotes
> + let mut value = lit.to_string();
> + if value.starts_with('"') && value.ends_with('"') {
> + value.remove(0);
> + value.pop();
> + }
> + segments.push((value, lit.span()));
> + }
> Some(TokenTree::Ident(ident)) => {
> let mut value = ident.to_string();
> if value.starts_with("r#") {

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