Le 15/05/2017 à 15:37, Martin Maechler a écrit :
Serguei Sokol <so...@insa-toulouse.fr>
on Mon, 15 May 2017 13:14:34 +0200 writes:
> I see in the archives that the attachment cannot pass.
> So, here is the code:
[....... MM: I needed to reformat etc to match closely to
the current source code which is in
https://svn.r-project.org/R/trunk/src/library/base/R/stop.R
or its corresponding github mirror
https://github.com/wch/r-source/blob/trunk/src/library/base/R/stop.R
]
> Best,
> Serguei.
Yes, something like that seems even simpler than Peter's
suggestion...
It currently breaks 'make check' in the R sources,
specifically in tests/reg-tests-2.R (lines 6574 ff),
the new code now gives
> ## error messages from (C-level) evalList
> tst <- function(y) { stopifnot(is.numeric(y)); y+ 1 }
> try(tst())
Error in eval(cl.i, pfr) : argument "y" is missing, with no default
whereas previously it gave
Error in stopifnot(is.numeric(y)) :
argument "y" is missing, with no default
But I think that change (of call stack in such an error case) is
unavoidable and not a big problem.
It can be avoided but at price of customizing error() and warning() calls with
something like:
wrn <- function(w) {w$call <- cl.i; warning(w)}
err <- function(e) {e$call <- cl.i; stop(e)}
...
tryCatch(r <- eval(cl.i, pfr), warning=wrn, error=err)
Serguei.
--
I'm still curious about Hervé's idea on using switch() for the
issue.
Martin
> Le 15/05/2017 à 12:48, Serguei Sokol a écrit :
>> Hello,
>>
>> I am a new on this list, so I introduce myself very briefly:
>> my background is applied mathematics, more precisely scientific calculus
>> applied for modeling metabolic systems, I am author/maintainer of
>> few packages (Deriv, rmumps, arrApply).
>>
>> Now, on the subject of this discussion, I must say that I don't really
understand
>> Peter's argument:
>>
>> >>> To do it differently, you would have to do something like
>> >>>
>> >>> dots <- match.call(expand.dots=FALSE)$...
>> >>>
>> >>> and then explicitly evaluate each argument in turn in the caller
>> >>> frame. This amount of nonstandard evaluation sounds like it would
>> >>> incur a performance penalty, which could be undesirable.
>> The first line of the current stopifnot()
>> n <- length(ll <- list(...))
>> already evaluates _all_ of the arguments
>> in the caller frame. So to do the same only
>> on a part of them (till the first FALSE or NA occurs)
>> cannot be more penalizing than the current version, right?
>>
>> I attach here a slightly modified version called stopifnot_new()
>> which works in accordance with the man page and
>> where there are only two additional calls: parent.frame() and eval().
>> I don't think it can be considered as real performance penalty
>> as the same or bigger amount of (implicit) evaluations was
>> already done in the current version:
>>
>>> source("stopifnot_new.R")
>>> stopifnot_new(3 == 5, as.integer(2^32), a <- 12)
>> Error: 3 == 5 is not TRUE
>>> a
>> Error: object 'a' not found
>>
>> Best,
>> Serguei.
>>
>>
>> Le 15/05/2017 à 10:39, Martin Maechler a écrit :
>>>>>>>> Hervé Pagès <hpa...@fredhutch.org>
>>>>>>>> on Wed, 3 May 2017 12:08:26 -0700 writes:
>>> > On 05/03/2017 12:04 PM, Hervé Pagès wrote:
>>> >> Not sure why the performance penalty of nonstandard evaluation would
>>> >> be more of a concern here than for something like switch().
>>>
>>> > which is actually a primitive. So it seems that there is at least
>>> > another way to go than 'dots <- match.call(expand.dots=FALSE)$...'
>>>
>>> > Thanks, H.
>>>
>>> >>
>>> >> If that can't/won't be fixed, what about fixing the man page so it's
>>> >> in sync with the current behavior?
>>> >>
>>> >> Thanks, H.
>>>
>>> Being back from vacations,...
>>> I agree that something should be done here, if not to the code than at
>>> least to the man page.
>>>
>>> For now, I'd like to look a bit longer into a possible change to the
function.
>>> Peter mentioned a NSE way to fix the problem and you mentioned
switch().
>>>
>>> Originally, stopifnot() was only a few lines of code and meant to be
>>> "self-explaining" by just reading its definition, and I really would
like
>>> to not walk too much away from that original idea.
>>> How did you (Herve) think to use switch() here?
>>>
>>>
>>>
>>> >> On 05/03/2017 02:26 AM, peter dalgaard wrote:
>>> >>> The first line of stopifnot is
>>> >>>
>>> >>> n <- length(ll <- list(...))
>>> >>>
>>> >>> which takes ALL arguments and forms a list of them. This implies
>>> >>> evaluation, so explains the effect that you see.
>>> >>>
>>> >>> To do it differently, you would have to do something like
>>> >>>
>>> >>> dots <- match.call(expand.dots=FALSE)$...
>>> >>>
>>> >>> and then explicitly evaluate each argument in turn in the caller
>>> >>> frame. This amount of nonstandard evaluation sounds like it would
>>> >>> incur a performance penalty, which could be undesirable.
>>> >>>
>>> >>> If you want to enforce the order of evaluation, there is always
>>> >>>
>>> >>> stopifnot(A) stopifnot(B)
>>> >>>
>>> >>> -pd
>>> >>>
>>> >>>> On 3 May 2017, at 02:50 , Hervé Pagès <hpa...@fredhutch.org>
>>> >>>> wrote:
>>> >>>>
>>> >>>> Hi,
>>> >>>>
>>> >>>> It's surprising that stopifnot() keeps evaluating its arguments
>>> >>>> after it reaches the first one that is not TRUE:
>>> >>>>
>>> >>>> > stopifnot(3 == 5, as.integer(2^32), a <- 12) Error: 3 == 5 is
>>> >>>> not TRUE In addition: Warning message: In stopifnot(3 == 5,
>>> >>>> as.integer(2^32), a <- 12) : NAs introduced by coercion to integer
>>> >>>> range > a [1] 12
>>> >>>>
>>> >>>> The details section in its man page actually suggests that it
>>> >>>> should stop at the first non-TRUE argument:
>>> >>>>
>>> >>>> ‘stopifnot(A, B)’ is conceptually equivalent to
>>> >>>>
>>> >>>> { if(any(is.na(A)) || !all(A)) stop(...); if(any(is.na(B)) ||
>>> >>>> !all(B)) stop(...) }
>>> >>>>
>>> >>>> Best, H.
>>> >>>>
>>> >>>> --
>>> >>>> Hervé Pagès
>>> >>>>
>>> >>>> Program in Computational Biology Division of Public Health
>>> >>>> Sciences Fred Hutchinson Cancer Research Center 1100 Fairview
>>> >>>> Ave. N, M1-B514 P.O. Box 19024 Seattle, WA 98109-1024
>>> >>>>
>>> >>>> E-mail: hpa...@fredhutch.org Phone: (206) 667-5791 Fax: (206)
>>> >>>> 667-1319
>>> >>>>
>>> >>>> ______________________________________________
>>> >>>> R-devel@r-project.org mailing list
>>> >>>>
>>>
https://urldefense.proofpoint.com/v2/url?u=https-3A__stat.ethz.ch_mailman_listinfo_r-2Ddevel&d=DwIFaQ&c=eRAMFD45gAfqt84VtBcfhQ&r=BK7q3XeAvimeWdGbWY_wJYbW0WYiZvSXAJJKaaPhzWA&m=JwgKhKD2k-9Kedeh6pqu-A8x6UEV0INrcxcSGVGo3Tg&s=f7IKJIhpRNJMC3rZAkuI6-MTdL3GAKSV2wK0boFN5HY&e=
>>> >>>>
>>> >>>
>>> >>
>>>
>>> > -- Hervé Pagès
>>>
>>> > Program in Computational Biology Division of Public Health Sciences
>>> > Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N,
>>> > M1-B514 P.O. Box 19024 Seattle, WA 98109-1024
>>>
>>> > E-mail: hpa...@fredhutch.org Phone: (206) 667-5791 Fax: (206)
>>> > 667-1319
>>>
>>> > ______________________________________________
>>> > R-devel@r-project.org mailing list
>>> > https://stat.ethz.ch/mailman/listinfo/r-devel
>>>
>>> ______________________________________________
>>> R-devel@r-project.org mailing list
>>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>
> ______________________________________________
> R-devel@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
