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From: Oliver Kiddle <okiddle@yahoo.co.uk>
To: Zsh Users <zsh-users@zsh.org>
Cc: Christopher Browne <cbbrowne@gmail.com>, rahul <rahul2012@gmail.com>
Subject: Re: Higher order functions in zsh (article link)
Date: Thu, 07 Mar 2013 22:12:11 +0100	[thread overview]
Message-ID: <9685.1362690731@quattro> (raw)
In-Reply-To: <20130307190842.GA67680@redoubt.spodhuis.org>

Phil Pennock wrote:
> Why does this code have an eval in there?  It's:

I suspect that the eval was there to allow the command to include
arguments: e.g. map 'print -l' *
Using $=func_name will add word-splitting to get that back without
reintroducing the security flaw.

> Oh, and you need to quote the $@ to "$@" if you want to preserve empty
> elements -- whether you do or not depends on what you're mapping across,
> but I tend to think "present but empty" is distinct from "not present".

Actually "$@" is the default for a for loop so you don't need it. And I
can't see that the use of print and command-substitution gets you
anything unless I'm missing something. So:

function map {
    local func_name=$1 elem
    shift
    for elem; $=func_name "${elem}"        
} 

This is unrelated but it seems the warncreateglobal option does't warn
about variables created using a for loop. Does anyone know if that is
intentional or a bug?

Oliver


  reply	other threads:[~2013-03-07 21:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-07  5:25 rahul
2013-03-07 16:59 ` Christopher Browne
2013-03-07 19:08   ` Phil Pennock
2013-03-07 21:12     ` Oliver Kiddle [this message]
2013-03-08  8:40 ` Stephen Blott

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