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Re: Docs fix



On Oct 26, 10:02pm, TGAPE! wrote:
> Subject: Re: Docs fix
> > 
> >> Not exactly.  "$@" keeps empty arguments and independent of option and
> >> IFS settings, neither of which is true for $*.
> > 
> > Yes, but as I was just explaining privately to Phil, the context of his
> > change is "what zsh construct is most like using \!* in csh aliases?"
> > 
> > The best answer is $*, because you have to use \!*:q to get "$@" behavior
> > in csh.  An argument could be made that $==* is even better, but not "$@".
> 
> Who cares if it is the behavior that is most equivalent, when the
> behavior is not what they want?!?

The context here is the question about converting csh aliases to zsh.

Csh aliases DO HAVE the equivalent of the "$@" construct.  It's \!*:q.

If one has a CORRECTLY WORKING ALIAS that uses \!* without the :q, then
using "$@" in the replacement zsh function will *NOT* do what one wants,
in at least some circumstances.

In ANY OTHER CONTEXT, *especially* in shells scripts, everything that is
being said about "$@" being better is *absolutely* correct.  But it is
NOT correct in the FAQ question where Phil's patch changes it!

> But, to quote Zoltan,
> 
> >   It's good habbit to use "$@".  The use of $* is almost always wrong
> >   in bourne/korn shell scripts still people use that all the time.

A zsh function intended to replace a csh alias is not a bourne/korn script.
Otherwise I completely agree.

> Showing people how to mimic the broken behavior of their old shells is
> not necessarily a good way to win converts or friends.  However, I do
> think the FAQ should be modified to mention that no, this isn't the the
> exact same behavior, this is better.

Sigh.  Look.  The FAQ cannot possibly explain all circumstances in which
"$@" is correct.  When it's correct, it's better; when it's wrong, it's
not better.

> Btw, can you show even *one* case where a csh user really wants $*
> functionality and not "$@"?

Sure.  Warning, csh syntax follows.

alias   do      "\!* >&! did &"
alias   dopr    '\!* | lpr -J "\!:1"'

If you replace $* with "$@" when converting those aliases, you end up
quoting the word in the command position, which causes unexptected side
effects.

> And, even if $* by default acted exactly
> like "$@", it's a good idea to script so as to be complient with as many
> shells as is reasonable.

This is all wonderful advice, but completely out of context for the place
that Phil's patch made the change.



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