[Rd] [EXTERNAL] Re: NOTE: multiple local function definitions for ?fun? with different formal arguments

[Izmirlian, Grant (NIH/NCI) [E]]

Because functions get called and therefore, the calling sequence matters. It’s just protecting you from yourself, but as someone pointed out, there’s a way to silence such notes.
G


From: Hervé Pagès <hpages.on.github using gmail.com>
Sent: Tuesday, February 6, 2024 2:40 PM
To: Izmirlian, Grant (NIH/NCI) [E] <izmirlig using mail.nih.gov>; Duncan Murdoch <murdoch.duncan using gmail.com>; r-devel using r-project.org
Subject: Re: [EXTERNAL] Re: [Rd] NOTE: multiple local function definitions for ?fun? with different formal arguments


On 2/6/24 11:19, Izmirlian, Grant (NIH/NCI) [E] wrote:
The note refers to the fact that the function named ‘fun’ appears to be defined in two different ways.

Sure I get that. But how is that any different from a variable being defined in two different ways like in

    if (mode == 1)
        x <- -8
    else
        x <- 55

This is such a common and perfectly fine pattern. Why would this be considered a potential hazard when the variable is a function?

H.

From: Hervé Pagès <hpages.on.github using gmail.com><mailto:hpages.on.github using gmail.com>
Sent: Tuesday, February 6, 2024 2:17 PM
To: Duncan Murdoch <murdoch.duncan using gmail.com><mailto:murdoch.duncan using gmail.com>; Izmirlian, Grant (NIH/NCI) [E] <izmirlig using mail.nih.gov><mailto:izmirlig using mail.nih.gov>; r-devel using r-project.org<mailto:r-devel using r-project.org>
Subject: [EXTERNAL] Re: [Rd] NOTE: multiple local function definitions for ?fun? with different formal arguments


Thanks. Workarounds are interesting but... what's the point of the NOTE in the first place?

H.
On 2/4/24 09:07, Duncan Murdoch wrote:
On 04/02/2024 10:55 a.m., Izmirlian, Grant (NIH/NCI) [E] via R-devel wrote:


Well you can see that yeast is exactly weekday you have.  The way out is to just not name the result

I think something happened to your explanation...




toto <- function(mode)
{
     ifelse(mode == 1,
         function(a,b) a*b,
         function(u, v, w) (u + v) / w)
}

It's a bad idea to use ifelse() when you really want if() ... else ... .  In this case it works, but it doesn't always.  So the workaround should be


toto <- function(mode)
{
    if(mode == 1)
        function(a,b) a*b
    else
        function(u, v, w) (u + v) / w
}






________________________________
From: Grant Izmirlian <izmirlidroid using gmail.com><mailto:izmirlidroid using gmail.com>
Date: Sun, Feb 4, 2024, 10:44 AM
To: "Izmirlian, Grant (NIH/NCI) [E]" <izmirlig using mail.nih.gov><mailto:izmirlig using mail.nih.gov>
Subject: Fwd: [EXTERNAL] R-devel Digest, Vol 252, Issue 2

Hi,

I just ran into this 'R CMD check' NOTE for the first time:

* checking R code for possible problems ... NOTE
toto: multiple local function definitions for �fun� with different
   formal arguments

The "offending" code is something like this (simplified from the real code):

toto <- function(mode)
{
     if (mode == 1)
         fun <- function(a, b) a*b
     else
         fun <- function(u, v, w) (u + v) / w
     fun
}

Is that NOTE really intended? Hard to see why this code would be
considered "wrong".

I know it's just a NOTE but still...

I agree it's a false positive, but the issue is that you have a function object in your function which can't be called unconditionally.  The workaround doesn't create such an object.

Recognizing that your function never tries to call fun requires global inspection of toto(), and most of the checks are based on local inspection.

Duncan Murdoch

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Hervé Pagès



Bioconductor Core Team

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Hervé Pagès



Bioconductor Core Team

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CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and are confident the content is safe.


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