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To: Zsh Users <zsh-users@zsh.org>
From: Ray Andrews <rayandrews@eastlink.ca>
Subject: &&||
Message-id: <64c5472a-b174-00b6-7ab0-b65d664be675@eastlink.ca>
Date: Mon, 19 Feb 2018 13:12:20 -0800
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function test ()
{
     _aaray=`ls`
     [ true ] && { print -l "${ _aaray[@]}" | GREP_COLOR='01;33' egrep 
--color=always "$1"\

| GREP_COLOR='01;31' egrep --color=always "$2" }\

|| echo bust!
}

    $ touch present

    $ test present pres
    present                            << two colors.

    $ test present pppres
    bust!

    $ test pppresent p
    bust!


When I first did this, I was puzzled by the output, then I wisely 
realized that the  '||'  was in fact responding to the return value of 
the failed egrep.  At first I did this without the braces and was 
content with what happened but I'd expect the braces to force the '||' 
to respond to the leading test (which of course never varies here being 
true all the time) and thus never give me a 'bust!' regardless of the 
egrep return value.  I solved the issue by using an 'if/else' 
construction but still I'm curious about the above.  Is my expectation 
mistaken?  Within an '&& ||' construction how would I write that to do 
as I was expecting -- respond to the truth value of the initial test?  
When I use braces in complex '&& ||' situations they always seem to 
behave as expected.  I do have the niggling feeling my expectation above 
is wrong, but I can't quite say why.