R help - Jun 2017 - Wrong function when import from module using get

Hi,

I found this issue:

when I have 3 modules:

* AnalysisA
* AnalysisB
* AnalysisC

I load all modules at the beginning from list of modules:

analyses <- list('AnalysisA', 'AnalysisB',
'AnalysisC')

for (module in analyses) {
   library(module, character.only = TRUE)
}

and I want to add a function isValid to each module, but I've added it only
for AnalysisB. When I run this code:

# value <- <selected by user>

flags <- sapply(analyses, function(module) {
    namespace <- getNamespace(module)
    tryCatch({
        isValid <- get("isValid", namespace)
        isValid(value)
    }, error = function(e) {
        TRUE
    })
})

# show analyses

analyses[flags]

then when R call get for AnalysisA it throw error, for AnalysisB it
return function but for AnalysisC it return function from AnalysisB and
don't
throw error.

As a workaround instead of tryCatch I've used:

if ("isValid" %in% ls(namespace)) {
    isValid <- get("isValid", namespace)
    isValid(value)
} else {
    TRUE
}

Is this a bug? Should this be reported?

I'm using R 3.4.0 on windows.

--
Jakub Jankiewicz, Web Developer
http://jcubic.pl/me

By module I mean a package instaled using:

R CMD INSTAL /path/

On Tue, 27 Jun 2017 10:06:16 +0200
Jakub Jankiewicz <jcubic at jcubic.pl> wrote:
> Hi,
> 
> I found this issue:
> 
> when I have 3 modules:
> 
> * AnalysisA
> * AnalysisB
> * AnalysisC
> 
> I load all modules at the beginning from list of modules:
> 
> analyses <- list('AnalysisA', 'AnalysisB',
'AnalysisC')
> 
> for (module in analyses) {
>    library(module, character.only = TRUE)
> }
> 
> and I want to add a function isValid to each module, but I've added it
only
> for AnalysisB. When I run this code:
> 
> # value <- <selected by user>
> 
> flags <- sapply(analyses, function(module) {
>     namespace <- getNamespace(module)
>     tryCatch({
>         isValid <- get("isValid", namespace)
>         isValid(value)
>     }, error = function(e) {
>         TRUE
>     })
> })
> 
> # show analyses
> 
> analyses[flags]
> 
> then when R call get for AnalysisA it throw error, for AnalysisB it
> return function but for AnalysisC it return function from AnalysisB and
> don't throw error.
> 
> As a workaround instead of tryCatch I've used:
> 
> if ("isValid" %in% ls(namespace)) {
>     isValid <- get("isValid", namespace)
>     isValid(value)
> } else {
>     TRUE
> }
> 
> Is this a bug? Should this be reported?
> 
> I'm using R 3.4.0 on windows.
> 
> --
> Jakub Jankiewicz, Web Developer
> http://jcubic.pl/me
--
Jakub Jankiewicz, Web Developer
http://jcubic.pl/me