Empty function

In mathematics , especially in set theory , an empty function is a function whose domain is the empty set . There is exactly one such function for every set ${\displaystyle A}$

${\displaystyle f_{A}\colon \emptyset \rightarrow A}$.

The graph of an empty function is the empty set.

proof

• Horst Herrlich, George E. Strecker: Category Theory. Heldermann Verlag (2007, English).