Method calling question...

[satchboost]

I've got the following setup:

Base.pm:
package Base;
sub method1 {
    # Insert code here
};

Foo.pm:
package Foo;
use Base;
@ISA = qw(Base);

Bar.pm:
package Bar;
use Base;
@ISA = qw(Base);

Main.pm
...
foreach my $classname qw(Foo Bar) {
    $classname->method1;
}

I know that this code doesn't work. What I'm wondering is what will work for what I'm trying to do?

[MeowChow]

I don't see what the problem is:

package Base;
sub method1 {
    # Insert code here
    print "Called from class: ", shift, "\n";
};

package Foo;
@ISA = qw(Base);

package Bar;
@ISA = qw(Base);

package main;

foreach my $classname qw(Foo Bar) {
    $classname->method1;
}

## Output ##

Called from class: Foo
Called from class: Bar

   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

[satchboost]

There's a reason I was using four files. If you have everything in one file, of course it works cause method1 is scoped within the file. When you have it across several files, it breaks down. :(

[MeowChow]

It's not a scoping issue:

foreach my $classname qw(Foo Bar Oops) {
    $classname->method1;
}

## output ##

Can't locate object method "method1" via package "Oops" at C:\Projects
+\GPerl\Test\2.pl line 16.
Called from class: Foo
Called from class: Bar

   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

[tye]

I can think of a few reasons why this might fail.

First, I don't see any require Foo nor require Bar (or replace require with use).

Second, you can replace @ISA= qw(Base) with use base qw(Base) which has some advantages. But I have more important reasons for mentioning that: On file systems that ignore upper- vs. lower-case in file names, use Base could end up loading base.pm instead of Base.pm, which would also break your code.

        - tye (but my friends call me "Tye")

[jplindstrom]

Second, you can replace @ISA= qw(Base) with use base qw(Base)

This sounds very interesting. Could you point me to a man page about this (or explain a little more about what Perl mechanism that makes it work)?

/J

[merlyn]

That'd be described in perldoc base, wouldn't it? Have you looked there first?

-- Randal L. Schwartz, Perl hacker

---

update: This dropped two points immediately after posting, so here's another "personality vote" potential candidate list:

tilly
btrott
jcwren
lhoward
MeowChow
BigJoe
Beatnik
Macphisto
jplindstrom
jlp
LD2
Kanji
isotope
kandinsky
batmonk
joee
koolade
UberGeek
prion

I'll get enough of these and start performing an intersection.

[spaz]

    "On file systems that ignore upper- vs. lower-case in file names, use Base could end up loading base.pm instead of Base.pm..."

Uhm, no.

If the file system is case-insensitive, then Base.pm == base.pm.

-- Dave

[tye]

Perhaps you neglect to consider that require and use search more than one directory. If Base.pm is in your current directory, then base.pm from the standard Perl install will be found and used instead of your file.

        - tye (but my friends call me "Tye")