Remove the deprecated unstable concat_idents! macro
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`concat_idents!` is in the process of being removed, but a few things it is used to test will still be relevant. Migrate these tests to something other than `concat_idents`.
These tests were updated in the previous commit; while they are being cleaned up, move them to a non-issue directory.
In [rust-lang#137653], the lang and libs-API teams did a joint FCP to deprecate and eventually remove the long-unstable `concat_idents!` macro. The deprecation is landing in 1.88, so do the removal here (target version 1.90). This macro has been superseded by the more recent `${concat(...)}` metavariable expression language feature, which avoids some of the limitations of `concat_idents!`. The metavar expression is unstably available under the [`macro_metavar_expr_concat`] feature. History is mildly interesting here: `concat_idents!` goes back to 2011 when it was introduced with 513276e ("Add #concat_idents[] and #ident_to_str[]"). The syntax looks a bit different but it still works about the same: let asdf_fdsa = "<.<"; assert(#concat_idents[asd,f_f,dsa] == "<.<"); assert(#ident_to_str[use_mention_distinction] == "use_mention_distinction"); (That test existed from introduction until its removal here.) Closes: rust-lang#29599 [rust-lang#137653]: rust-lang#137653 [`macro_metavar_expr_concat`]: rust-lang#124225
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This shouldn't need any specific approval because of the completed FCP at #137653 (comment), but just as a heads up: @rust-lang/lang @rust-lang/libs |
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should we do a crater run? |
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I don't think we necessarily need to act on any crater results, since anyone using this should already be getting the deprecation warnings. But it also doesn't hurt to see what those results might be. @bors2 try |
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Remove the deprecated `concat_idents!` macro In [#137653], the lang and libs-API teams did a joint FCP to deprecate and eventually remove the long-unstable `concat_idents!` macro. The deprecation is landing in 1.88, so do the removal here (target version 1.90). This macro has been superseded by the more recent `${concat(...)}` metavariable expression language feature, which avoids some of the limitations of `concat_idents!`. The metavar expression is unstably available under the [`macro_metavar_expr_concat`] feature. History is mildly interesting here: `concat_idents!` goes back to 2011 when it was introduced with 513276e ("Add #concat_idents[] and #ident_to_str[]"). The syntax looks a bit different but it still works about the same: let asdf_fdsa = "<.<"; assert(#concat_idents[asd,f_f,dsa] == "<.<"); assert(#ident_to_str[use_mention_distinction] == "use_mention_distinction"); (That test existed from introduction until its removal here.) Closes: #29599 [#137653]: #137653 [`macro_metavar_expr_concat`]: #124225
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concat_idents! macroconcat_idents! macro
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In rust-lang/rust#137653, the lang and libs-API teams did a joint FCP to deprecate
and eventually remove the long-unstable
concat_idents!macro. Thedeprecation is landing in 1.88, so do the removal here (target version
1.90).
This macro has been superseded by the more recent
${concat(...)}metavariable expression language feature, which avoids some of the
limitations of
concat_idents!. The metavar expression is unstablyavailable under the
macro_metavar_expr_concatfeature.History is mildly interesting here:
concat_idents!goes back to 2011when it was introduced with 513276e ("Add #concat_idents[] and
#ident_to_str[]"). The syntax looks a bit different but it still works
about the same:
(That test existed from introduction until its removal here.)
Closes: #29599