Define subvalues for a symbol f:

These are the subvalues associated with f:

SubValues returns rules corresponding to subvalues defined for a symbol:

SubValues can be defined for heads of any depth:

Create several values:

Obtain the subvalues of functions whose names start with f:

SubValues can be used to set the values directly:

Create a data object for properties that can be extracted:

These definitions are stored as SubValues:

Extract all the properties from a given object:

The resulting rules are in the order given:

Now reorder the definitions:

Copy a symbol's definitions to another symbol:

Values can be defined by immediate or delayed assignments:

HoldPattern is used to protect the rules from their own definitions:

Without the HoldPattern, the left-hand side would have evaluated:

SubValues["sym"] will issue a message if the specified symbol does not exist:

If the symbol exists but has no definitions, an empty list is returned:

Definition and Information display subvalues but do not return them as values:

SubValues returns a value that can be used in a program:

Evaluation of an expression involves applying matching subvalues: