Alternative S4 Constructor

Usage

new2(class, ...)

Arguments

class

Class name to instanciate

...

extra arguments from which slot values are extracted by exact matching of names.

Examples

setClass('A', contain='character', representation(x='numeric', y='character'))
# identical behaviour with standard calls
identical(new('A'), new2('A'))

[1] TRUE
identical(new('A', x=1), new2('A', x=1))

[1] TRUE
# but if passing that are names not slots
identical(new('A'), new2('A', b=1))

[1] TRUE
identical(new('A', x=1), new2('A', x=1, b=3))

[1] TRUE
identical(new('A', x=1), new2('A', x=1, b=3))

[1] TRUE
# standard `new` would coerce first unnamed argument into parent of 'A' (i.e. 'character')
new('A', list(x=1))

An object of class "A"
[1] "1"
Slot "x":
numeric(0)

Slot "y":
character(0)

new('A', list(x=1, y='other'))

An object of class "A"
[1] "1"     "other"
Slot "x":
numeric(0)

Slot "y":
character(0)

# `new2` rather use it to initialise the slots it can find in the list
identical(new('A', x=1), new2('A', list(x=1)))

[1] TRUE
identical(new('A', x=1, y='other'), new2('A', list(x=1, y='other')))

[1] TRUE