all.equal applied to function closures
One more comment: it might be worthwhile reporting on a case where identical(e1, e2) fails when those are the environments associated with two functions (though I think not by default in all.equal.environment). Functions can modify variables in their environment, so examples like the open.account example in the R-intro manual would distinguish between ross and robert even if the balances matched. Duncan Murdoch
On 01/12/2020 10:37 a.m., Bill Dunlap wrote:
Probably all.equal.environment's do1() could be enhanced to do the recursion (and look at the environments' attributes).? I wrote a separate function because it was easier to experiment that way (e.g., when to stop recursing?- it stops when one environment is a top-level environment or the empty environment).? I've been thinking about similar recursion options for ls.str() - it would make it easier to debug refClass and R6 code where the data is somewhere in a stack of environments.
> E1 <- list2env(list(X=1.1, Y=1.2), parent=list2env(list(p=1.3),
parent=baseenv()))
> E2 <- list2env(list(X=1.1, Y=1.2), parent=list2env(list(p=1.4),
parent=baseenv()))
> base::all.equal.environment(E1,E2)
[1] TRUE
> globalenv()$all.equal.environment(E1,E2)
[1] "<parent.env> Component ?p?: Mean relative difference: 0.07692308"
> > E3 <- list2env(list(X=1.1, Y=1.2), parent=list2env(list(p=1.5),
parent=new.env(parent=baseenv())))
> base::all.equal.environment(E1,E3)
[1] TRUE
> globalenv()$all.equal.environment(E1,E3)
[1] "<parent.env> Component ?p?: Mean relative difference: 0.1538462" [2] "<parent.env> <parent.env> target is <environment: base> and current is <environment: 0x564e806705c8>" On Tue, Dec 1, 2020 at 1:31 AM Martin Maechler <maechler at stat.math.ethz.ch <mailto:maechler at stat.math.ethz.ch>> wrote:
>>>>> Bill Dunlap
>>>>>? ? ?on Mon, 30 Nov 2020 13:41:54 -0800 writes:
? ? > To make the comparison more complete, all.equal.environment
could compare
? ? > the parents of the target and current environments.? That
would have to be
? ? > recursive but could stop at the first 'top level environment'
(the global,
? ? > empty, or a package-related environment generally) and use
identical
? ? > there.? E.g.,
? ? > > f1 <- function(x) (function(){ expx <- exp(x) ; function(y)
y + expx})()
? ? > > all.equal(f1(2), f1(3))
? ? > [1] "Environments: Component ?expx?: Mean relative
difference: 1.718282"
? ? >
? ? > [2] "Environments: <parent.env> Component ?x?: Mean relative
difference:
? ? > 0.5"
? ? > This is from the following, where I avoided putting the existing
? ? > non-recursive all.equal.environment into the body of this one.
? ? > all.equal.environment <-
? ? > function(target, current, ...)
? ? > {
? ? >? ? ?.all.equal.environment <- base::all.equal.environment #
temporary hack
? ? >? ? ?stopifnot(is.environment(target), is.environment(current))
? ? >? ? ?if (identical(target, current)) {
? ? >? ? ? ? ?TRUE
? ? >? ? ?} else {
? ? >? ? ? ? ?msg <- NULL # TODO: check attributes
? ? >? ? ? ? ?# deal with emptyenv now since parent.env(emptyenv())
gives error
? ? >? ? ? ? ?# and topenv(emptyenv()) gives GlobalEnv
? ? >? ? ? ? ?eTarget <- identical(target, emptyenv()) ||
? ? > identical(target,topenv(target))
? ? >? ? ? ? ?eCurrent <- identical(current, emptyenv()) ||
? ? > identical(current,topenv(current))
? ? >? ? ? ? ?if (eTarget || eCurrent) {
? ? >? ? ? ? ? ? ?msg <- c(msg, paste("target is", format(target),
"and current
? ? > is", format(current)))
? ? >? ? ? ? ?} else {
? ? >? ? ? ? ? ? ?thisComparison <- .all.equal.environment(target,
current, ...)
? ? >? ? ? ? ? ? ?if (!isTRUE(thisComparison)) {
? ? >? ? ? ? ? ? ? ? ?msg <- c(msg, thisComparison)
? ? >? ? ? ? ? ? ?}
? ? >? ? ? ? ? ? ?parentComparison <- Recall(parent.env(target),
? ? > parent.env(current), ...)
? ? >? ? ? ? ? ? ?if (!isTRUE(parentComparison)) {
? ? >? ? ? ? ? ? ? ? ?msg <- c(msg, paste("<parent.env>",
parentComparison))
? ? >? ? ? ? ? ? ?}
? ? >? ? ? ? ?}
? ? >? ? ? ? ?if (is.null(msg) || isTRUE(msg)) TRUE else msg
? ? >? ? ?}
? ? > }
Thank you, Duncan and Bill (and Kevin for bringing up the
topic).
I agree? all.equal() should work better with functions,
and I think probably it would make sense to define? all.equal.function()
rather than put this into all.equal.default()
However, it's not quite clear if it is always desirable to check the
environments as well notably as that *is* done recursively.
Bill, I'm sure you've noticed that we did write? all.equal.environment()
to work recursively... Actually, I had worked quite a bit at
that, too long ago to remember details, but the relevant svn log
entry is
------------------------------------------------------------------------
r66640 | maechler | 2014-09-18 22:10:20 +0200 (Thu, 18 Sep 2014) | 1
line
more sophisticated all.equal.environment(): no longer "simple"
infinite recursions
------------------------------------------------------------------------
Are you sure that code with the internal recursive do1()
function should/could not be amended where needed?
Martin
? ? > On Mon, Nov 30, 2020 at 10:42 AM Duncan Murdoch
<murdoch.duncan at gmail.com <mailto:murdoch.duncan at gmail.com>>
? ? > wrote:
? ? >
? ? > > On 30/11/2020 1:05 p.m., Kevin Van Horn via R-devel wrote:
? ? > > > Consider the following code:
? ? > > >
? ? > > >? ? ? f <- function(x)function(y){x+y}
? ? > > >? ? ? all.equal(f(5), f(0))
? ? > > >
? ? > > > This returns TRUE, when it should return FALSE; I think
it?s hard to
? ? > > make the case that f(5) and f(0) are ?approximately equal?
in any
? ? > > meaningful sense. Digging into the code for all.equal(), I
see that
? ? > > all.equal(f(5), f(0)) results in a call to
all.equal.language(f(5), f(0)),
? ? > > which only compares the function texts for equality.
? ? > > >
? ? > > > If it is decided to leave this behavior as-is, then at
least it should
? ? > > be documented. Currently I cannot find any documentation
for all.equal
? ? > > applied to functions.
? ? > >
? ? > > Clearly it should also compare the environments of the two
functions,
? ? > > then it would see a difference:
? ? > >
? ? > >? > all.equal(environment(f(5)), environment(f(0)))
? ? > > [1] "Component ?x?: Mean relative difference: 1"
? ? > >
? ? > > Changing the first few lines from
? ? > >
? ? > >? ? ? if (is.language(target) || is.function(target))
? ? > >? ? ? ? ? return(all.equal.language(target, current, ...))
? ? > >
? ? > > to
? ? > >
? ? > >? ? ? if (is.function(target)) {
? ? > >? ? ? ? ? msg <- all.equal.language(target, current, ...)
? ? > >? ? ? ? ? if (isTRUE(msg)) {
? ? > >? ? ? ? ? ? ? msg <- all.equal.environment(environment(target),
? ? > > environment(current), ...)
? ? > >? ? ? ? ? ? ? if (is.character(msg))
? ? > >? ? ? ? ? ? ? ? msg <- paste("Environments:", msg)
? ? > >? ? ? ? ? }
? ? > >? ? ? ? ? return(msg)
? ? > >? ? ? }
? ? > >? ? ? if (is.language(target))
? ? > >? ? ? ? ? return(all.equal.language(target, current, ...))
? ? > >
? ? > > would fix it.
? ? > >
? ? > > Duncan Murdoch
? ? > >
? ? > > ______________________________________________
? ? > > R-devel at r-project.org <mailto:R-devel at r-project.org>
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? ? > > https://stat.ethz.ch/mailman/listinfo/r-devel
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