R devel - Mar 2006 - Error once having applied (PR#8718)

Hi, people.  Here is a transcript of a "R --vanilla" session:

======================================================================>

R : Copyright 2005, The R Foundation for Statistical Computing
Version 2.2.1  (2005-12-20 r36812)
ISBN 3-900051-07-0

R est un logiciel libre livr?? sans AUCUNE GARANTIE.
Vous pouvez le redistribuer sous certaines conditions.
Tapez 'license()' ou 'licence()' pour plus de d??tails.

R est un projet collaboratif avec de nombreux contributeurs.
Tapez 'contributors()' pour plus d'information et
'citation()' pour la fa??on de le citer dans les publications.

Tapez 'demo()' pour des d??monstrations, 'help()' pour
l'aide
en ligne ou 'help.start()' pour obtenir l'aide au format HTML.
Tapez 'q()' pour quitter R.
> z = data.frame(a=0:9, b=10:19)
> apply(z, 1, sum)
 1  2  3  4  5  6  7  8  9 10
10 12 14 16 18 20 22 24 26 28
> apply(z, 1, '$', 'a')
NULL
> apply(z, 1, sum)
Erreur dans sum(..., na.rm = na.rm) : 'mode' de l'argument incorrect
======================================================================<

There are three explicit calls to "apply", one would expect the first
and the third to yield similar results.  They do indeed, if the second
"apply" is not executed, or if '$' gets replaced by
'[[' within it.  So
the second "apply", as written, may be hurting the R interpreter.

--please do not edit the information below--

Version:
 platform = i686-pc-linux-gnu
 arch = i686
 os = linux-gnu
 system = i686, linux-gnu
 status = 
 major = 2
 minor = 2.1
 year = 2005
 month = 12
 day = 20
 svn rev = 36812
 language = R

Locale:
LC_CTYPE=fr_CA.UTF-8;LC_NUMERIC=C;LC_TIME=fr_CA.UTF-8;LC_COLLATE=fr_CA.UTF-8;LC_MONETARY=fr_CA.UTF-8;LC_MESSAGES=fr_CA.UTF-8;LC_PAPER=C;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=C;LC_IDENTIFICATION=C

Search Path:
 .GlobalEnv, package:methods, package:stats, package:graphics,
package:grDevices, package:utils, package:datasets, Autoloads, package:base

Merci, Fran?ois!
>>>>> "FrPi" == Fran?ois Pinard <pinard at
progiciels-bpi.ca>
>>>>>     on Tue, 28 Mar 2006 03:00:19 +0200 (CEST) writes:
    FrPi> Hi, people.  Here is a transcript of a "R --vanilla"
session:
    FrPi>
======================================================================>

    FrPi> R : Copyright 2005, The R Foundation for Statistical Computing
    FrPi> Version 2.2.1  (2005-12-20 r36812)

    ....................

    >> z = data.frame(a=0:9, b=10:19)
    >> apply(z, 1, sum)
    FrPi> 1  2  3  4  5  6  7  8  9 10
    FrPi> 10 12 14 16 18 20 22 24 26 28
    >> apply(z, 1, '$', 'a')
    FrPi> NULL
    >> apply(z, 1, sum)
    FrPi> Erreur dans sum(..., na.rm = na.rm) : 'mode' de
l'argument incorrect
    FrPi>
======================================================================<

    FrPi> There are three explicit calls to "apply", one would
expect the first
    FrPi> and the third to yield similar results.  They do indeed, if the
second
    FrPi> "apply" is not executed, or if '$' gets replaced
by '[[' within it.  So
    FrPi> the second "apply", as written, may be hurting the R
interpreter.

Indeed! 'z' itself is not changed; it's something else that's
corrupted,
since one can reproduce the bug by

apply(data.frame(a=0:9, b=10:19), 1, sum)
apply(data.frame(a=0:9, b=10:19), 1, "$", "a")
apply(data.frame(a=0:9, b=10:19), 1, sum)
##-> error ... invalid 'mode'

This also happens in "R-devel", since yesterday aka 
"2.3.0 alpha".

Martin