Re: ${(q)...} for newline

[Peter Stephenson <Peter.Stephenson@xxxxxxx>]

On Tue, 25 May 2010 14:25:13 +0100
Stephane Chazelas <stephane_chazelas@xxxxxxxx> wrote:
> 2010-05-23 21:45:39 +0100, Peter Stephenson:
> > Also, would I be right in thinking this is an accident waiting to
> > happen?
> > 
> > % foo=(one '' three)
> > % print ${(q)foo}
> > one three
>
> Not in the first case though, as array expansion removes the
> empty elements.

I don't think that argument really works... consider:

% foo=(one '' three)
% print ${(j.X.)foo}
oneXXthree

In other words, flags are applied before empty elements are
stripped.  The same goes for most transformations on array elements,
whether zsh-specific or otherwise; I don't see why (q) should be
different.

However, we don't actually say in the (already long) manual entry giving
the rules for variable expansion at what part either quoting or empty
element removal takes place.  The latter appears to be the last thing of all,
i.e. at the point where we decide to insert this into the list of arguments
(or otherwise).  I should probably concoct something.


Bart wrote
> However, I suggest that (q-) continue to use the literal quoted newline.

Right, it's really there as minimal quoting for human readability.

-- 
Peter Stephenson <pws@xxxxxxx>            Software Engineer
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