Re: Invisible PROMPT2

On Wed, Nov 13, 2019 at 03:58:38PM -0300, Alvaro Herrera wrote:
> On 2019-Nov-13, David Fetter wrote:
>
> > On Wed, Nov 13, 2019 at 03:06:08PM -0300, Alvaro Herrera wrote:
> > > On 2019-Nov-13, David Fetter wrote:
> > >
> > > > On Wed, Nov 13, 2019 at 09:47:01AM -0500, Tom Lane wrote:
> > >
> > > > > > How about a circumfix directive (like the existing %[ ... %])
> > > > > > that replaces everything inside with whitespace, but keeps the width?
>
> > > This seems way too specific to me. I like the "circumfix" directive
> > > better, because it allows one to do more things. I don't have any
> > > immediate use for it, but it doesn't seem completely far-fetched that
> > > there are some.
>
> > So something like %w[...%w] where people could put things like PROMPT1
> > inside?
>
> Hmm, (I'm not sure your proposed syntax works, but let's assume that
> it does.) I'm saying you'd define
> \set PROMPT1 '%a%b%c '
> \set PROMPT2 '%w[%a%b%c %w]'
>
> and you'd end up with matching indentation on multiline queries.
>
> I'm not sure that we'd need to make something like this work:
> PROMPT1="%w[$PROMPT1%w]"
> which I think is what you're saying.

PROMPT2="%w[$PROMPT1%w]", and basically yes.

> We already have "%:PROMPT1:" but that expands to the literal value of
> prompt1, not to the value that prompt1 would expand to:

Yeah, that's not so great for this usage. I guess "expand variables"
could be a separate useful feature (and patch) all by itself...

Best,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778

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