Re: Re: Re: Re: Re: Calling can method

When can't you call $x->can('foo') safely? When $x can't can(), of course!

for $x ('main', undef, \1) {

  if (UNIVERSAL::can($x, 'can')) {

    # ok

    print "can can\n";
    $x->can('foo');
    print "\n";

  } else {

    # error: Can't call method "can" on undefined value/unblessed refe
+rence ...

    print "can't can\n";
    eval { $x->can('foo') };
    print "$@\n";

  }

}
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(tye)Re: Calling can method by tye (Sage) on May 30, 2001 at 22:25 UTC
Clarification: The else part wouldn't generate an error for `'main'` but would/does for the other two (well, it wasn't clear to me at first but I think that is more my problem than chipmunk's). One case you didn't mention is "strings that don't start with a \w character": `$x= 'fred'; print $x->can('can'); Can't call method "can" without a package or object reference` [download] and, yes, it is (currently, at least) only the first character that matters for this test. BTW, these errors are fatal (which is why chipmunk used eval, otherwise the loop would not have continued). Updated* many times while I tried to make some sense. - tye (but my friends call me "Tye")	[reply] [d/l] [select]

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(tye)Re: Calling can method
by tye (Sage) on May 30, 2001 at 22:25 UTC

Clarification: The else part wouldn't generate an error for 'main' but would/does for the other two (well, it wasn't clear to me at first but I think that is more my problem than chipmunk's).

One case you didn't mention is "strings that don't start with a \w character":

$x= '*fred';
print $x->can('can');

Can't call method "can" without a package or object reference
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BTW, these errors are fatal (which is why chipmunk used eval, otherwise the loop would not have continued).

Updated many times while I tried to make some sense.

tye

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