Re: Question about MP3::Tag and undef id3v2

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Re^2: Question about MP3::Tag and undef id3v2 by DecMoon (Novice) on Sep 05, 2017 at 17:50 UTC
Hmm, no, it's commented because there is no id3v2 : `$VAR1 = \undef; Can't call method "get_frame_ids" on an undefined value at ./test.pl l +ine 26.` [download] That's why I do `my $id3v2 = exists $mp3->{ID3v2} ? $mp3->{ID3v2} : $mp3->new_tag("ID3v2");`	[reply] [d/l] [select]
Re^3: Question about MP3::Tag and undef id3v2 by kcott (Archbishop) on Sep 06, 2017 at 06:12 UTC
G'day DecMoon, Welcome to the Monastery. These are lines `25` and `26` in the code you posted: `print Dumper(\$id3v2); print Dumper(\$id3v2->get_frame_ids);` [download] The first line of output you show (`$VAR1 = \undef;`) is telling you that `$id3v2` is `undef` (i.e. it's undefined). So, "`$id3v2->get_frame_ids`" (in line `26`) is equivalent to "`undef->get_frame_ids`". That's effectively what the second line of output you show is telling you. You'll need to do something with your assignment to `$id3v2`. I'm unfamiliar with the `MP3::Tag` module, so I'm not really in a position to advise you what that "something" might be. Options could include: checking for definedness; setting a default value; skipping some part of the code if it's not defined; or something completely different. — Ken	[reply] [d/l] [select]