bug#47902: cperl-mode: unwanted expansion of '$continue' [PATCH]

[Harald Jörg]

The symptom: When typing "$continue", abbrev expansion kicks in and
converts this to "$continue { }" - which immediately catches the eye as
suddenly it is formatted as a hash access.

How to reproduce from Emacs -Q:

    C-x b demo.pl <RET>
    M-: (setq cperl-electric-keywords t)
    cperl-mode <RET>
    $continue = 1;

It is quite usual to activate 'cperl-electric-keywords', either directly
or with the catch-all customization value 'cperl-hairy'.

Root cause: The expansion routine in 'cperl-electric-else' attempts to
verify that the keyword starts a statement, by jumping back over the
keyword with (backward-sexp 1).  For a scalar variable "$else" or
"$continue", this expression also skips back over the dollar (which has
syntax type "escape" in CPerl mode), and "$continue" does start a
statement, so unwanted expansion happens.

The patch replaces (backward-sexp 1) by (skip-chars-backward "[:alpha:]")
and avoids skipping over anything which doesn't belong to the keyword.

-- 
Cheers,
haj

0001-cperl-mode-Avoid-abbrev-expansion-in-variable-names.patch
Description: Avoid expansion of "$continue"