[Rd] match.arg confusion (PR#921)

p.dalgaard@biostat.ku.dk p.dalgaard@biostat.ku.dk
Thu, 26 Apr 2001 01:01:52 +0200 (MET DST)

[sys.function fails sometimes (sorry, our mail system decide to throw
away the original mail)]

Yes, I bumped into something similar recently. The problem is that we
only actually store the call in the context structure, not the
function, so sys.function has to grab the call, take the 1st element,
and reevaluate it in the parent frame. It is quite easy to think up
examples where a second evaluation does not give the same value as
the first. 

Your particular case is of a slightly different natur and should be
easily fixable by replacing findVar in R_sysfunction by findVar1 and
looking specifically for objects of mode "function", but the basic
problem persists. I don't think I want to risk fixing this (and maybe
unfixing something else) for 1.2.3 tomorrow though.

   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard@biostat.ku.dk)             FAX: (+45) 35327907

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