cottrell@nbs-vms.ARPA (02/05/85)
/* > > int ptr[] <=> int *ptr > > Oo, oo! This brings to mind a useful language extension: > > a <=> b; > > for exchanging the contents of a and b. How often have you written: > > { register type t; > > t = a; > a = b; > b = t; > } Rarely. I use: `a ^= b; b ^= a; a ^= b;' Only worx for integer types. */
guy@rlgvax.UUCP (Guy Harris) (02/05/85)
> > How often have you written: > > > > { register type t; > > > > t = a; > > a = b; > > b = t; > > } > Rarely. I use: `a ^= b; b ^= a; a ^= b;' Only worx for integer types. Also takez more cycles on most machines. An example: on the 68000, case 1 is move.l a,t # 32-bit ints move.l b,a move.l t,a case 2 is move.l b,d0 eor.l d0,a move.l a,d0 eor.l d0,b move.l b,d0 eor.l d0,a Cute, but not worth it. Guy Harris {seismo,ihnp4,allegra}!rlgvax!guy