As I'm moving forward with the new PIL runcore, I'm now trying to document my understanding as visual diagrams. Today I produced two:
While the first one is (I hope) self-explanatory, the second one requires some explanation. All the lines in it are has-a relationships; Pad has-a Scalar Container that you can look up with $name:
my $name;The Container either has-a mutable cell, or has-a constant cell:
my $mut = 3; my $con := 3;
Use := to change the cell inside a container:
my $x = 3; my $y = 4; my $z = 5; $x := $y; # $x and $y now contain the same cell $x := $z; # not anymore; $x now shares the cell with $z
Each cell has-a Id. Use =:= to check whether two containers have cells of the same Id:
$x =:= $y; # false $x =:= $z; # true
Mutable cells has-a mutable scalar value. Use = to change its value:
$mut = 5; # works
Constant cells has-a immutable scalar value. You cannot change it:
$con = 6; # error
Each cell is declared to be is Tieable or not tieable when it was allocated; you cannot change tieableness at runtime.
my $nvar; my $tvar is Tieable;
Tieable cells may be tied or untied. Use tie to tie a tieable cell:
tie($tvar, SomeClass, some_param => 1);
Non-tieable cells may not be tied. However, untie always works:
untie($tvar); # works untie($nvar); # no-op
That's about it for today. I hope you enjoy the pictures. :-)
Re:Pictures
autrijus on 2005-08-07T16:03:55
Visio, with the excellent Nuvola icon set. Previously I've produced SVK at a glance with the same set of tools.Re:Pictures
malte on 2005-08-08T06:32:59
Damn, Visio. I hoped I missed the announcement of Apple's new easy to use graphics tool for superior looking pictures:)
