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Date: Tue, 23 Jan 2018 17:10:42 +0000
From: Eric Wong <normalperson@yhbt.net>
To: ruby-core@ruby-lang.org
Message-ID: <20180123171042.GA14355@starla>
References: <redmine.issue-14385.20180123110351@ruby-lang.org>
 <redmine.journal-69698.20180123134620.789a782e1431f4f1@ruby-lang.org>
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Subject: [ruby-core:85011] Re: [Ruby trunk Feature#14385] Deprecate
 back-tick for Ruby 3.
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nobu@ruby-lang.org wrote:
> Matz's intention is to use back-ticks for a different syntax,
> not to deprecate the command substitution feature.

I think that is dangerous to have the meaning of any syntax element
become something else, even removing it entirely would be less bad.

I have some scripts which are not used for several years at a
time, so they may never be run during the 2.x cycle.  Having
back-tick do something entirely different in 3.x can give a
false positive on success, that potentially causes data loss or
corruption.

False positives is worse than complete failure of a script.


That said, I see back-ticks are used improperly all the time.
For example, I would support adding warnings and suggestions to
use system() instead of being used in a void context.  Dangerous
interpolation would be one use case for keeping taint, even.