Because the S3 class system is very informal. E.g. if you happen to
have an `if.whatever` function, that will be automatically a method of
your generic.
Gabor
On Sat, Mar 4, 2017 at 7:49 PM, Da Zheng wrote:
> I'm just curious. Why making "if" generic is even more dangerous?
>
> Best,
> Da
>
> On
Here's a patch that enables the error if
_R_CHECK_CONDITION_={1,true,TRUE,yes,YES}.
$ svn diff
Index: src/main/eval.c
===
--- src/main/eval.c (revision 72303)
+++ src/main/eval.c (working copy)
@@ -1851,9 +1851,19 @@
Rboolean con
dplyr::translate_sql() redefines lots of functions, include "if", to
translate from R syntax to SQL syntax.
> dplyr::translate_sql(if ("mpg">25) "better" else "worse")
CASE WHEN ('mpg' > 25.0) THEN ('better') ELSE ('worse') END
Bill Dunlap
TIBCO Software
wdunlap tibco.com
On Sat, Mar 4, 2017 a
In my case, I create a new type of matrices and override matrix
operations in R for these matrices.
My goal is to make the system as transparent as possible, which means
my system should execute the existing R code without modification.
The problem is that when data is in my own vectors or matrices
I'm curious as to precisely why someone would want to do this.
On Sat, Mar 4, 2017 at 11:49 AM, Da Zheng wrote:
> I'm just curious. Why making "if" generic is even more dangerous?
>
> Best,
> Da
>
> On Sat, Mar 4, 2017 at 1:22 PM, Gábor Csárdi
> wrote:
> > `!` is a generic, `if` is not. You can
Is there really a need for these complications? Packages emitting this
warning are broken by definition and should be fixed. Perhaps we could
"flip the switch" in a test environment and see how much havoc is wreaked
and whether authors are sufficiently responsive?
Michael
On Sat, Mar 4, 2017 at 1
> Henrik Bengtsson
> on Fri, 3 Mar 2017 10:10:53 -0800 writes:
> On Fri, Mar 3, 2017 at 9:55 AM, Hadley Wickham
> wrote:
>>> But, how you propose a warning-to-error transition
>>> should be made without wreaking havoc? Just flip the
>>> switch in R-devel and see
I'm just curious. Why making "if" generic is even more dangerous?
Best,
Da
On Sat, Mar 4, 2017 at 1:22 PM, Gábor Csárdi wrote:
> `!` is a generic, `if` is not. You can define an `if` that is generic,
> but this might be even more dangerous
>
> ❯ `if` <- function(a, b, c) UseMethod("if")
> ❯
`!` is a generic, `if` is not. You can define an `if` that is generic,
but this might be even more dangerous
❯ `if` <- function(a, b, c) UseMethod("if")
❯ `if.default` <- function(a,b,c) base::`if`(a, b, c)
❯ `if.foo` <- function(a, b, c) FALSE
❯ a <- structure(42, class = "foo")
❯ if (a) TRU
Thanks.
Can I override it for a specific class?
I can do that for operators such as "!". For example, "!.fm" works for
objects of the class "fm".
It seems I can't do the same for "if".
Best,
Da
On Sat, Mar 4, 2017 at 12:41 PM, Gábor Csárdi wrote:
> You can. Perhaps needless to say, be careful wi
You can. Perhaps needless to say, be careful with this.
❯ `if` <- function(...) FALSE
❯ if (TRUE) TRUE else FALSE
[1] FALSE
G.
On Sat, Mar 4, 2017 at 5:36 PM, Da Zheng wrote:
> Hello,
>
> I heard we can override almost everything in R. Is it possible to
> override "if" keyword in R to evaluate
Hello,
I heard we can override almost everything in R. Is it possible to
override "if" keyword in R to evaluate my own object instead of a
logical value?
Thanks,
Da
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