[R] When using require(), why do I get the error message "Error in if (!loaded) { : the condition has length > 1" ?

[Jeff Newmiller]

Don't load base. It is already loaded.

On October 24, 2022 9:07:44 AM PDT, Kelly Thompson <kt1572757 using gmail.com> wrote:
># Below, when using require(), why do I get the error message "Error
>in if (!loaded) { : the condition has length > 1" ?
>
># This is my reproducible code:
>
>#create a vector with the names of the packages I want to use
>packages_i_want_to_use <- c('base', 'this_pac_does_not_exist')
>
># Here I get error messages:
>require( packages_i_want_to_use[1] )
>#Error in if (!loaded) { : the condition has length > 1
>
>require( packages_i_want_to_use[2] )
>#Error in if (!loaded) { : the condition has length > 1
>
># Here I get what I expect:
>require('base')
>
>require('this_pac_does_not_exist')
>#Loading required package: this_pac_does_not_exist
>#Warning message:
>#In library(package, lib.loc = lib.loc, character.only = TRUE,
>logical.return = TRUE,  :
>#  there is no package called ‘this_pac_does_not_exist’
>
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-- 
Sent from my phone. Please excuse my brevity.