Enumeration ReferenceType

The identifier is defined by an argument (which we know nothing about at the moment)

The identifier is defined by a built-in value/constant

The identifier is defined by a built-in function

The identifier is defined by a constant (includes built-in constant)

The identifier is defined by a function (includes built-in function)

Only ever a lookup target, never the type of a definition: everything a value position may see.

The identifier is defined by a parameter (which we know nothing about at the moment)

Prefix to identify S3 methods, use this, to for example dispatch a call to f which will then link to f.*

Prefix to identify S7 methods, use this, to for example dispatch a call to f which will then link to f<7>*

The identifier type is unknown

The identifier is defined by a variable (includes parameter and argument)