Re^2: Do I need to use defined?

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Re^3: Do I need to use defined? by roboticus (Chancellor) on Sep 07, 2017 at 06:02 UTC
Uh ... because 0 is defined. ...roboticus When your only tool is a hammer, all problems look like your thumb.	[reply]
Re^3: Do I need to use defined? by Anonymous Monk on Sep 07, 2017 at 06:19 UTC
In Perl, three things are false: the undefined value (`undef`), the empty string (`''`), and zero (`0`). Two of those things are `defined`.	[reply]
Re^4: Do I need to use defined? by afoken (Chancellor) on Sep 07, 2017 at 06:49 UTC
Empty arrays and hashes are also false: `>perl -E 'my @a=(); my @a2=@a or say "FALSE"' FALSE >perl -E 'my %h=(); my %h2=%h or say "FALSE"' FALSE >perl -E 'my @a=(0); my @a2=@a or say "FALSE"' >perl -E 'my %h=(""=>0); my %h2=%h or say "FALSE"' >` [download] Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l]
Re^5: Do I need to use defined? by Anonymous Monk on Sep 07, 2017 at 06:56 UTC
Empty arrays and hashes become zero in scalar context, and zero is false.	[reply]
Re^6: Do I need to use defined? by afoken (Chancellor) on Sep 07, 2017 at 07:04 UTC
Re^7: Do I need to use defined? by Anonymous Monk on Sep 07, 2017 at 07:22 UTC
Re^7: Do I need to use defined? by Anonymous Monk on Sep 07, 2017 at 07:33 UTC