[tcltk-perl] overload stringification of widgets

[Vadim K. <va...@ar...>]

As you may have noticed, I did a change to make for any widget to be its
path when stringification occurs.
so
perl -MTcl::Tk -we "$i =Tcl::Tk::tkinit->Button->pack; print $i"
outputs
.btn01


Interesting to say, it required adding just one line to Tk.pm:

  use overload '""' => \&path;

Now code from tk-demo like
    my $f_list = $f->Listbox;
    my $f_scroll = $f->Scrollbar(-command => [$f_list => 'yview']);

works via stringification of $f_list.

However, I wonder if there will be any consequences (I mean slowdown).
If anyone notices this, please speak.

Using "Benchmark.pm" Perl module:
I commented line "MainLoop" in 'wdiget' from 'tk-demo' directory, and here
it is:

w/o overload:
>perl -MBenchmark -e "timethis 100, sub{do 'widget0'}"
timethis 100:  6 wallclock secs ( 5.28 usr +  0.59 sys =  5.87 CPU) @
17.04/s (n=100)
>perl -MBenchmark -e "timethis 300, sub{do 'widget0'}"
timethis 300: 17 wallclock secs (15.12 usr +  1.27 sys = 16.39 CPU) @
18.30/s (n=300)

w/ overload:
>perl -MBenchmark -e "timethis 100, sub{do 'widget0'}"
timethis 100:  6 wallclock secs ( 5.38 usr +  0.56 sys =  5.94 CPU) @
16.84/s (n=100)
>perl -MBenchmark -e "timethis 300, sub{do 'widget0'}"
timethis 300: 16 wallclock secs (15.19 usr +  1.19 sys = 16.38 CPU) @
18.31/s (n=300)

Now same with perlTk:
widget0-ptk is 'widget' from distribution perlTk804-024, with three lines
commented out:
#use lib Tk->findINC('demos/widget_lib');
...
#use WidgetDemo;
...
#MainLoop;

perl -MBenchmark -e "timethis 100, sub{do 'widget0-ptk'}"
timethis 100: 19 wallclock secs (17.70 usr +  1.41 sys = 19.11 CPU) @
5.23/s (n=100)
300:
timethis 300: 57 wallclock secs (51.57 usr +  4.61 sys = 56.18 CPU) @
5.34/s (n=300)

Best regards,
Vadim.