:: deftheorem Def11 defines modid TMAP_1:def 11 :
for X being non empty TopSpace
for X0 being SubSpace of X
for b₃ being Function of X,(X modified_with_respect_to X0) holds
( b₃ = modid (X,X0) iff for A being Subset of X st A = the carrier of X0 holds
b₃ = modid (X,A) );