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From: Ilkka Virta <itvirta@iki.fi>
Newsgroups: gnu.bash.bug
Subject: Re: Tilde expansion in assignment-like context
Date: Tue, 7 Aug 2018 08:39:25 +0300
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On 6.8. 22:45, Chet Ramey wrote:
> Yes. Bash has done this since its earliest days. A word that looks like an
> assignment statement has tilde expansion performed after unquoted =~ and :~
> no matter where it appears on the command line. 

Given that options starting with a double-dashes (--something=/some/dir) 
are rather common, would it make sense to extend tilde expansion to 
apply in that case too?

Of course, getopt_long() supports giving the option argument in a 
separate command-line argument, so you can work around it with that.


Also, does the documentation actually say tilde expansion applies in 
anything that looks like an assignment? I can only see "If a word begins 
with an unquoted tilde character..." and "Each variable assignment is 
checked for unquoted tilde-prefixes...", but from the shell language 
point of view, the one in 'make DESTDIR=~stager/bash-install' isn't an 
assignment, just a regular command line argument.

The paragraph about assignments could be expanded to say "This applies 
also to regular command-line arguments that look like assignments." or 
something like that.


-- 
Ilkka Virta / itvirta@iki.fi