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tractor.base (version 1.6.0)

list.object: The list.object class

Description

The list.object class is inherited by the MriImage and MriImageMetadata classes and takes the general form of a list of functions with associated frame containing data fields. isListObject tests for this class, and print.list.object prints an object of this class.

Usage

isListObject(object)
## S3 method for class 'list.object':
print(x, ...)

Arguments

object
Any object.
x
Object of class list.object.
...
Further options to print (though none are supported for this type of object).

Value

  • isListObject returns TRUE if object is a list object. print.list.object is only called for its side-effect.

Details

The list.object class is the basis for various other classes in the TractoR packages. The class itself inherits from list. The isListObject function can be used to test whether a given object is a list object or not. print.list.object calls the summarise function within the list object if one is defined; otherwise it prints the result of calling summary(object), which will give a list of functions in the object.

See Also

At the time of writing, section 10.7 of "An Introduction to R", on scope, gives an example of the principle behind the object-as-a-list-of-functions approach used here.