Both of these answers ignored that the sub was an 'anonymous'/'inline' sub that would have access to surrounding local variables in the same scope, including regex vars.

I find it surprising that '$1' is affected in this way by an anonymous sub.

I wouldn't find it surprising that a normal sub would auto-save context to not completely disrupt callers (even though '$_' needs to be explicitly saved with local).

To re-ask, why is an inline-sub which I thought was designed to have access to local vars (in same context) restoring '$1'. If it was accessing or changing '$_1', it would access the copy of the sub it was in. I had supposed that the '$1' would stay constant until another regex and that an inline/anon sub wouldn't treat '$1' differently from '$_1'.

I was really more wondering what the rational might be for treating them differently in an anon/inline sub.

In the same way I find that '$1', and '$2' are cleared coming out of a 'do' block to be strange -- I would have thought only another regex would change them. 

my $s="abcdefg";
$_=$s;
my @res=do { m{abc(de)(fg)}; };
P "nres=%s 1=%s, 2=%s", 0+@res, $1, $2;
'
nres=2 1=∄, 2=∄

In reply to Re^2: why is $1 cleared at end of an inline sub? by perl-diddler
in thread why is $1 cleared at end of an inline sub? by perl-diddler

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.