DOLLAR.Class {R.oo} | R Documentation |
Makes the fields and methods of an Class accessible via the $ and the [[ operator
Description
Makes the fields and methods of an Class accessible via the $
operator. This method is never called explicitly, but through an indirect
usage of the $
operator, e.g. obj$name
or
obj$getValue()
.
This method will first search for a
get<Name>()
method, e.g. if name has the value"age"
, agetAge()
will be looked for. If such a method exists it will be called with the Class as the first and only argument, e.g.getAge(this)
. Aget<Name>()
is only looked for if<name>
is not a private field. A private field is a name beginning with a.
(period). The rational for this naming convention is to be consistent with howls()
works, which will not list such members by default.If no such method exists, first then, this method will look a field in the Class can has the name
name
.If such neither exists, a method with name
name
will be searched for and returned.If no fields or methods are found at all,
NULL
is returned.
Usage
## S3 method for class 'Class'
this$name
## S3 method for class 'Class'
this[[name, exact=TRUE]]
Arguments
name |
The name of the field or method to be accessed. |
... |
Not used. |
Value
Returns the value of a field or a method (function
).
If no such field or method exists, NULL
is returned.
Author(s)
Henrik Bengtsson
See Also
For more information see Class
.
Examples
## Not run: For a complete example see help(Class).