package yDebug; BEGIN { $file = 'trace.out'; # disable tracing while setting things up $Devel::Trace::TRACE = 0; } sub import { shift; $file = shift if @_ } CHECK { $Devel::Trace::FORMAT = "# line %d %s: %s"; @Devel::Trace::ORDER = (2,0,3); open MYFH, '>', $file or die "open '$file': $!"; $Devel::Trace::FH = *MYFH; # enable tracing for package Foo $Devel::Trace::PKG{Foo}++; # done, enable tracing $Devel::Trace::TRACE = 1; } 1;