Syntax definition wfo

Description: Extend the definition of a wff to include onto functions. (Read: F maps A onto B .) The notation ("onto" below the arrow) is from Definition 6.15(4) of TakeutiZaring p. 27.

	Ref	Expression
Assertion	wfo	wff 𝐹 : 𝐴 –onto→ 𝐵