bug#19281: 11.86; environment update fails when environment name contains \

[Tassilo Horn]

Mosè Giordano <address@hidden> writes:

>> I tried to update an environment in a latex document via C-u C-c C-e
>> or LaTeX-modify-environment but mistyped the name as 'theorem\'. I
>> tried to correct my error via C-u C-c C-e again but I got a search
>> failed message:
>>
>> LaTeX-modify-environment: Search failed: "\\\\end{ *\\([a-zA-Z*]*\\)}"
>
> I can confirm the bug you reported.  Indeed, `\begin' and `\end'
> accept as valid environment names macros (not your case though) and
> macros with arguments,

Oh, indeed.

> while `LaTeX-modify-environment' searches for names matching
> "[a-zA-Z*]".  So, I'm not sure how to fix it: Just add `TeX-esc' to
> the regexp?

That and TeX-grop, TeX-grcl, and [] for optional args, no?

> Or matching everything between the opening and the closing brace
> (allowing at least one level of braces)?

Either that, or we could also rely on syntax tables.  I.e., since
`LaTeX-find-matching-end' already brings us to the end of the
environment name,

  (let ((end (point)))
    (forward-char)
    (backward-sexp)
    (forward-char)
    (buffer-substring-no-properties (point) end))

gives us the environment name.

Bye,
Tassilo