Piers Cawley wrote: > Unless I'm very much mistaken, the order of execution will > look like: > > $2:=$1; $1:=$2;
You're not binding $2:=$1. You're binding $2 to the first capture. By default $1 is also bound to the first capture. Assuming that numbered variables aren't special, the order of execution is: $2:=$1:=first; $1:=$2:=second; That doesn't make any sense though, so numbered variables must be treated specially -- an explicit numbered binding replaces the default numbered binding. So, the order of execution is really: $2:=first; $1:=second; I think this solves both of your puzzles. One last thing though. Binding might be done at compile-time because it changes variables, not the values of variables. Thinking about binding as a compile-time declaration might be easier than thinking about run-time execution order. Thinking about binding as a compile-time thing, the rule / $2:=(\S+) <lt>= $1:=(\S+) / becomes / <begin $2>[\S+]<end $2> <lt>= <begin $1>[\S+]<end $1> / - Ken
