Re^2: Code from perlboot not working as expected

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Re^3: Code from perlboot not working as expected by kennethk (Abbot) on May 17, 2010 at 14:49 UTC
Ahh, I missed that part of the OP - sorry. That's happening because the first object in `@_` when you invoke a method via an object is the object, not the package name. Thus your `$class` variable contains the scalar reference and when you print `$class` you stringify that reference. One way of handling that is to use ref. Something like: `my $self = shift; my $class = ref($self) \|\| $self;` [download] If `$self` contains a blessed reference, `ref` will return the package name. If it contains a string, `ref` will return `undef` and hence the `\|\|` will return the original string. I personally prefer perltoot to perlboot. But both are certainly worth working through.	[reply] [d/l] [select]
Re^4: Code from perlboot not working as expected by davies (Monsignor) on May 17, 2010 at 15:10 UTC
Perfect. I actually tried perltoot first, but got horribly confused by constructs like `my $class = ref($self) \|\| $self;`. Thanks to your explanation, I now understand that, too. I also see from trying the suggestion in Re^3: Code from perlboot not working as expected how to get a reference to the name, another point that was causing me confusion. Thanks and regards, John Davies	[reply] [d/l]
Re^3: Code from perlboot not working as expected by Anonymous Monk on May 17, 2010 at 14:51 UTC
$class is a reference to the object and I believe that's what you get when you print out a reference. Just dereference it (note the double $): print "a $$class goes ", $class->sound, "!\n"; Kevin Sigl	[reply]
Re^4: Code from perlboot not working as expected by kennethk (Abbot) on May 17, 2010 at 15:00 UTC
Dereferencing will get you the value contained in the scalar reference, but the spec expects the package name. The code `print "a $$class goes ", $class->sound, "!\n";` will yield the output `a Mr. Ed goes neigh!` not the expected `a Horse goes neigh!` It will also fail outright if the code is invoked statically, with the error under strict: `Can't use string ("Horse") as a SCALAR ref while "strict refs" in use`	[reply] [d/l] [select]