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From: "Procházka Lukáš Ing. - Pontex s. r. o." <LPr@pontex.cz>
To: ConTeXt <ntg-context@ntg.nl>
Subject: Number of pages by Lua of a figure to be inserted?
Date: Wed, 10 Apr 2013 16:22:24 +0200	[thread overview]
Message-ID: <op.wvbwvmr3tpjj8f@lpr> (raw)

Hello,

I need to identify number of pages by Lua of an image which is to be inserted.

The image can be of all various types supported by Ctx - e.g. .png, .pdf.

I've been using the following code so far (based on a mailing thread in the past):

----
function nOfPages(fn)
   local fig = figures.push{name = fn}
     local info = figures.identify()

     figures.check()

     local n = fig.used.pages
   figures.pop()

   return n
end
----

But the code above break Ctx in the case that the image doesn't exist.

I'd need to modify the solution somehow so to return 'nil' or 'false' (or a error message) in the case the file was not found.

How to do it?

TIA.

Best regards,

Lukas

(NB: Still "ConTeXt  ver: 2012.11.26 13:31 MKIV  fmt: 2012.11.27  int: english/english".)


-- 
Ing. Lukáš Procházka [mailto:LPr@pontex.cz]
Pontex s. r. o.      [mailto:pontex@pontex.cz] [http://www.pontex.cz]
Bezová 1658
147 14 Praha 4

Tel: +420 244 062 238
Fax: +420 244 461 038

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             reply	other threads:[~2013-04-10 14:22 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-04-10 14:22 Procházka Lukáš Ing. - Pontex s. r. o. [this message]
2013-04-10 15:38 ` Hans Hagen
2013-04-11  7:10   ` Procházka Lukáš Ing. - Pontex s. r. o.

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