Fetch an Attribute

This function differs from rlang::%@% in that it stops if the attribute doesn't exist.

Usage

x %@% a

Arguments

x

an R object (variable with attributes)

a

the name of an attribute

Value

the value of the attribute: attr(x,a)

Details

This function tries to find a similarly named attribute disregarding capitalization and using partila matching.

The only way from this function to return NULL is when x is null (the object that supposedly has the attribute). For the purposes of this function , NULL objects are treated as optional things, and thus their attributes do not matter. Non-NULL objects that should have an attribute, but don't are considered erroneous.