Add some clarifications and fixes for fmt syntax #151013
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This tries to clarify a few things regarding fmt syntax: - The comment on `Parser::word` seems to be wrong, as that underscore-prefixed words are just fine. This was changed in rust-lang#66847. - I struggled to follow the description of the width argument. It referred to a "second argument", but I don't know what second argument it is referring to (which is the first?). Either way, I rewrote the paragraph to try to be a little more explicit, and to use shorter sentences. - The description of the precision argument wasn't really clear about the distinction of an Nth argument and a named argument. I added a sentence to try to emphasize the difference. - `IDENTIFIER_OR_KEYWORD` was changed recently in rust-lang/reference#2049 to include bare `_`. But fmt named arguments are not allowed to be a bare `_`.
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Kivooeo
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Jan 12, 2026
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This tries to clarify a few things regarding fmt syntax:
Parser::wordseems to be wrong, as that underscore-prefixed words are just fine. This was changed in Allow any identifier as format arg name #66847.IDENTIFIER_OR_KEYWORDwas changed recently in Change underscore to be a keyword reference#2049 to include bare_. But fmt named arguments are not allowed to be a bare_.