Functions to check if an object is a keyvalue object, or coerce it if
possible.
Usage
as.keyvalue(x, ...)
# S3 method for data.frame
as.keyvalue(x, standard_var_names = NULL, ...)
# S3 method for default
as.keyvalue(x, y, ...)
is.keyvalue(x)
Arguments
x
object to test for, or coerce to, keyvalue (see the details).
...
arguments passed between methods
standard_var_names
a character vector with standard names for
variables decoded with this key-values.
y
a value vector if x is an unnamed vector (argument must be
named 'y = .')
Value
as.keyvalue returns a data.frame with additional class
keyvalue that fulfills the requirements for a keyvalue object
and with the key column as character. It also has two extra attributes
standard_var_names as described above and keyvalue11 which is
TRUE for keyvalue objects with a 1:1 relation between its keys and
values (otherwise FALSE).
Details
x can be of:
a name of a package internal (or
external) keyvalue object (character of length one)
a data.frame
with two columns "key" (with unique cells) and "value".