Re: Assigning Null to a variable

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Re^2: Assigning Null to a variable by AnomalousMonk (Archbishop) on Jul 02, 2012 at 15:34 UTC
I don't know enough about SQL to know how its `NULL` compares to Perl's undef, but it strikes me that "I know what the value is, and the value is: that it is known that it has no value at all" is actually a pretty good (Update: well, on second thought, perhaps just a bit wordy) explanation of our friend `undef`!	[reply] [d/l] [select]
Re^3: Assigning Null to a variable by afoken (Chancellor) on Jul 02, 2012 at 19:13 UTC
"I know what the value is, and the value is: that it is known that it has no value at all" is actually a pretty good explanation of our friend `undef`! ... and that's why DBI maps SQL's `NULL` to `undef` and vice versa. Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l] [select]
Re^2: Assigning Null to a variable by cavac (Prior) on Jul 02, 2012 at 15:10 UTC
You could still use it that way in arrays. For hashes there is "exists" vs. "defined", see `perldoc -f exists`. If haven't tested it now (working from memory and POD), but this looks like it fits the bill. Sorry for any bad spelling, broken formatting and missing code examples. During a slight disagreement with my bicycle (which i lost), i broke my left forearm near the elbow. I'm doing the best i can here...	[reply] [d/l]