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Re: GNU Bash v.4.4.23-5 built-in function 'set' produces variable outputs

From Robert Elz <kre@munnari.OZ.AU>
Newsgroups gnu.bash.bug
Subject Re: GNU Bash v.4.4.23-5 built-in function 'set' produces variable outputs
Date 2018-10-22 12:54 +0700
Message-ID <mailman.2569.1540187763.1284.bug-bash@gnu.org> (permalink)
References <CAMu=Brp3q_-GV2j7R+hbXZX8LLakhQGd1O0y64q0xB2UBRRO6g@mail.gmail.com> <CAM_8-CiC=2-wY+y9GpRutzuOhom3q5ayS54sdH=F_w106WMj4Q@mail.gmail.com> <20181019195026.mmtktfswn3evxvlw@eeg.ccf.org>

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    Date:        Fri, 19 Oct 2018 16:21:27 -0400
    From:        Grisha Levit <grishalevit@gmail.com>
    Message-ID:  <CAMu=Brp3q_-GV2j7R+hbXZX8LLakhQGd1O0y64q0xB2UBRRO6g@mail.gmail.com>

  | I guess it's a bit surprising that $_ is set to just the variable name
  | and not "the last argument to the previous command", which would be
  | the full assignment string.

Except that a var assign isn't a command at all, but something different, and
one could argue that with no command $_ should retain its value from whatever
was the last command.   But $_ has so many different uses in bash (and ksh93) 
and was a horrible botch in the first place (from when it was first added to 
ksh) so what it does isn't worth being concerned about - as best as can be
done, simply ignore it, and hope it eventually goes away....

kre

ps: it would be really nice if, in bash (and everywhere else) $_ could turn
into one of the magic vars which loses its special properties when unset.
Scripts that want to use $_ (if there are any, which I doubt) won't be
unsetting it and would continue to work, the rest of us (at least those of
us not insane enough to try and use it) could just "unset _" in .profile (etc)
and be done with it.

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Re: GNU Bash v.4.4.23-5 built-in function 'set' produces variable outputs Robert Elz <kre@munnari.OZ.AU> - 2018-10-22 12:54 +0700

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