Accessors/getters for DCElement objects

[mpadge]

In the absence of any accessors for DCElement objects, I would expect the only available method of simply naming them to return the actual objects. This leads to the following unexpected behaviour:

library(atom4R)
packageVersion ("atom4R")
#> [1] '0.2.9999'

a0 <- DCAvailable$new (value = FALSE)
ls (a0) # okay
#>  ... expected output

d <- atom4R::DCEntry$new ()
d$addDCAvailable ("01-01-0001")
d$validate ()
#> [atom4R][INFO] Object 'DCEntry' is VALID according to Atom XML schemas!
#> [1] TRUE
a1 <- d$available
ls (a1)
#> Error in list2env(list(<environment>), NULL, <environment>): names(x) must be a character vector of the same length as x

^{Created on 2022-05-18 by the reprex package (v2.0.1)}

Happens because of this line:

atom4R/R/DCEntry.R

Line 85 in 31a0645

self[[term]][[length(self[[term]])+1]] <- elem

Everything is embedded within a list, and trying to access elements as $<element> does not behave as expected. It would arguably be safer to provide accessor methods to (1) enable easy and systematic access; and (2) avoid unexpected behaviour like this.

[eblondel]

There is no 'getter' accessor, if i understand well what you mean by accessor. We can add some basic getter method for DCElement if needed to facilitate getting some element based on field. Assuming value is what defines the unicity of the element, we might name the list, but it's not always the case, as we may have xml attributes. I will look into that and let you know