:: deftheorem defines BorrowStr FSCIRC_1:def 4 :
for x, y, c being set holds BorrowStr (x,y,c) = (BorrowIStr (x,y,c)) +* (1GateCircStr (<*[<*x,y*>,and2a],[<*y,c*>,and2],[<*x,c*>,and2a]*>,or3));