Named List Members
We can assign names to list members, and reference them by names instead of numeric indexes.
For example, in the following, v is a list of two members, named "bob" and "john".
We retrieve a list slice with the single square bracket "" operator. Here is a list slice containing a member of v named "bob".
With an index vector, we can retrieve a slice with multiple members. Here is a list slice with both members of v. Notice how they are reversed from their original positions in v.
In order to reference a list member directly, we have to use the double square bracket "[]" operator. The following references a member of v by name.
A named list member can also be referenced directly with the "$" operator in lieu of the double square bracket operator.
We can attach a list to the R search path and access its members without explicitly mentioning the list. It should to be detached for cleanup.