Metamath Proof Explorer


Theorem pmex

Description: The class of all partial functions from one set to another is a set. (Contributed by NM, 15-Nov-2007)

Ref Expression
Assertion pmex ACBDf|FunffA×BV

Proof

Step Hyp Ref Expression
1 ancom FunffA×BfA×BFunf
2 1 abbii f|FunffA×B=f|fA×BFunf
3 xpexg ACBDA×BV
4 abssexg A×BVf|fA×BFunfV
5 3 4 syl ACBDf|fA×BFunfV
6 2 5 eqeltrid ACBDf|FunffA×BV