Re: Question regarding variable scope

[chimni]

When you declare my $black_player at the start of the sub .That variable is global through the scope of the sub .
(My or our would behave the same with respect to this sub,behaviour would vary with respect to code followinng down the line).
When you do a foreach $black_player (@possible_opponents)
This effectively overrides the above $black_player .It is local to the loop.Same principle as a pass by value in C.
Therefore ,you can rename your looping variable or just do what roger has done ,use $_.

[MarkM]

Actually, my() and our() do not behave the same from a subroutine. Both define a lexical context for the variable, however, my() allocates a new variable each time it is evaluated, while our() reuses a global.

For recursive subroutines, or subroutines that are accessed at the same time from multiple threads, my() variables are safe, while our() variables are unsafe.