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php is null or empty?
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What you're looking for is:
if($variable === NULL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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How to find the most recent file in a directory using .NET, and without looping?
I need to find the most recently modified file in a directory.
11 Answers
11
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ls command: how can I get a recursive full-path listing, one line per file?
How can I get ls to spit out a flat list of recursive one-per-line paths?
24 Answers
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Why are side-effects modeled as monads in Haskell?
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Suppose a function has side effects. If we take all the effects it produces as the input and output parameters, then the function is pure to the outside world.
So, for an impure function
f' :: Int -> Int
we add the RealWorld to the...
How do you specify a byte literal in Java?
If I have a method
6 Answers
6
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Is a GUID unique 100% of the time?
Is a GUID unique 100% of the time?
22 Answers
22
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What's the difference between globals(), locals(), and vars()?
What is the difference between globals() , locals() , and vars() ? What do they return? Are updates to the results useful?
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PHP's array_map including keys
Is there a way of doing something like this:
18 Answers
18
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What does the `forall` keyword in Haskell/GHC do?
I'm beginning to understand how the forall keyword is used in so-called "existential types" like this:
8 Answers
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Multiprocessing: How to use Pool.map on a function defined in a class?
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I also was annoyed by restrictions on what sort of functions pool.map could accept. I wrote the following to circumvent this. It appears to work, even for recursive use of parmap.
from multiprocessing import Process, Pipe
from itertools import izip
def spawn(f):
def fu...