postponed processing

[Henning Hraban Ramm <hraban@fiee.net>]

Me again...
I'd like to define an address layer in my environment:

--- start env --

\definelayer[senderlayer]
	[x=0mm, y=0mm, width=\paperwidth, height=\paperheight]

\def\Sender#1#2#3{\setvalue{SenderKey#1}{#2}\setvalue{SenderVal#1}{#3}}
\def\GetSenderLine#1{\bTR\bTD\doiftextelse{\getvalue{SenderKey#1}}%
	{\getvalue{SenderKey#1}:}{}\eTD\bTD\getvalue{SenderVal#1}\eTD\eTR}

\setlayerframed[senderlayer]
	[%corner={right}, location={left,bottom},
	x=\dimexpr(\getvalue{LogoHOffset}-\bleed), %\getvalue{LogoHOffset},
	y=\getvalue{LogoHeight}] % \dimexpr(\getvalue{LogoHeight}+\topspace)
	[height=46mm, width=\dimexpr(\getvalue{SenderKeyWidth}+\getvalue 
{SenderValueWidth}),
	frame=off, offset=none, align={left,top}]{%
	\setupTABLE[frame=off]
	\setupTABLE[x][1][width=\getvalue{SenderKeyWidth}, align=left, style= 
{\keystyle\strut}]
	\setupTABLE[x][2][width=\getvalue{SenderValueWidth}, align=right,  
style={\valstyle\strut}]
	\bTABLE
	\dostepwiserecurse{1}{9}{1}{% count from 1 to 9, step 1
		\expanded{\GetSenderLine{\recurselevel}}
	}
	\eTABLE
}

\def\EnableSender{\setupbackgrounds[rightpage][page]
	[background={\currentvalue, senderlayer}]}

--- stop env ---

and use that later in a product/component:

--- start text ---

\Sender{1}{Name}{Hraban}
\Sender{2}{Web}{www.fiee.net}

\EnableSender

--- stop text ---

Of course it doesn't work, because the Sender values aren't set via  
typesetting the address in the environment, and \x1c\currentvalue in  
\EnableSender hasn't the right value either.

Holger solves this in his letter style (wiki) via setups.
Is that the best approach?
How else could I postpone the senderlayer processing?
(I guess it would work with some expansion magic, but I'd like to  
stay at ConTeXt's surface as much as possible.)


Grüßlis vom Hraban!
---
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