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Re: Some general purpose PostScript procedures - multiget scanpath straccum strfinish

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On Wednesday, April 15, 2020 at 12:30:27 AM UTC-5, luser droog wrote:
> On Tuesday, April 14, 2020 at 6:17:41 PM UTC-5, ne...@zzo38computer.org.invalid wrote:
> > As part of TeXnicard, I wrote many PostScript procedures. Many of them are
> > not usable outside of TeXnicard, but a few of them are. Maybe you might
> > find some of them useful; I don't know. But I found it useful.
> > 
> > The multiget procedure is used to retrieve multiple entries from a
> > dictionary, and put them into an array. It might be useful with
> > writeobject or with some other things too. (Unfortunately, this
> > implementation does not work with objects other than dictionaries, since
> > known is only compatible with dictionaries.)
> > 
> > /multiget {  %( dict array -- array )
> >   << >> begin
> >   exch /A exch def
> >   /B 1 index length def
> >   {
> >     A 1 index known {
> >       A exch get
> >     } {
> >       pop null
> >     } ifelse
> >   } forall
> >   B array astore
> >   end
> > } bind def
> > 
> 
> Interesting stuff. I came up with a shorter version of this which doesn't
> need a local dict. But it doesn't work with bind since it modifies the
> internal proc.
> 
> /map { [ 3 1 roll forall ] } def
> /mg {
>     { DICT exch { get } stopped { pop pop null } if }
>     dup 0  5 -1 roll put  map
> } def

I got it to work with bind. Gotta curry a new array instead of modifying.

/mg { % dict [keys]  -  [values]
    exch 
    { exch { get } stopped { pop pop null } if }
    /exec cvx
    3 array astore cvx
    map
} bind def

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Some general purpose PostScript procedures - multiget scanpath straccum strfinish news@zzo38computer.org.invalid - 2020-04-14 16:17 -0700
  Re: Some general purpose PostScript procedures - multiget scanpath straccum strfinish luser droog <luser.droog@gmail.com> - 2020-04-14 22:30 -0700
    Re: Some general purpose PostScript procedures - multiget scanpath straccum strfinish luser droog <luser.droog@gmail.com> - 2020-04-16 23:02 -0700

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