reconsider MM = MetrStruct(# the carrier of M, the distance of M #) as MetrSpace by Lm1;
take
MM
; ( the carrier of MM c= the carrier of M & ( for x, y being Point of MM holds the distance of MM . (x,y) = the distance of M . (x,y) ) )
thus
the carrier of MM c= the carrier of M
; for x, y being Point of MM holds the distance of MM . (x,y) = the distance of M . (x,y)
let x, y be Point of MM; the distance of MM . (x,y) = the distance of M . (x,y)
thus
the distance of MM . (x,y) = the distance of M . (x,y)
; verum