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What does “dereferencing” a pointer mean?
Please include an em>x m>ample with the em>x m>planation.
6 Answers
6
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Null vs. False vs. 0 in PHP
...The var has not been initialized.
False means "not true in a boolean contem>x m>t". Used to em>x m>plicitly show you are dealing with logical issues.
0 is an int. Nothing to do with the rest above, used for mathematics.
Now, what is tricky, it's that in dynamic languages like PHP, all of them have a value ...
Element-wise addition of 2 lists?
... list2) )
[5, 7, 9]
or zip with a list comprehension:
>>> [sum(m>x m>) for m>x m> in zip(list1, list2)]
[5, 7, 9]
Timing comparisons:
>>> list2 = [4, 5, 6]*10**5
>>> list1 = [1, 2, 3]*10**5
>>> %timeit from operator import add;map(add, list1, list2)
10 loops, best of ...
Check if a number is int or float
...
Use isinstance.
>>> m>x m> = 12
>>> isinstance(m>x m>, int)
True
>>> y = 12.0
>>> isinstance(y, float)
True
So:
>>> if isinstance(m>x m>, int):
print 'm>x m> is a int!'
m>x m> is a int!
_EDIT:_
As pointed out, in case o...
Haskell composition (.) vs F#'s pipe forward operator (|>)
...eralizing let-bindings are sufficiently different as to affect this. For em>x m>ample, I know in F# sometimes writing
let f = em>x m>p
will not compile, and you need em>x m>plicit eta-conversion:
let f m>x m> = (em>x m>p) m>x m> // or m>x m> |> em>x m>p
to make it compile. This also steers people away from points-free/compos...
Why don't Java's +=, -=, *=, /= compound assignment operators require casting?
Until today, I thought that for em>x m>ample:
11 Answers
11
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Equivalent of Math.Min & Math.Mam>x m> for Dates?
What's the quickest and easiest way to get the Min (or Mam>x m>) value between two dates? Is there an equivalent to Math.Min (& Math.Mam>x m>) for dates?
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How do I list all files of a directory?
...rt walk
f = []
for (dirpath, dirnames, filenames) in walk(mypath):
f.em>x m>tend(filenames)
break
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Flatten an irregular list of lists
...re ( here , here , here , here ), but as far as I know, all solutions, em>x m>cept for one, fail on a list like this:
46 Answ...
Set environment variables on Mac OS m>X m> Lion
...
First, one thing to recognize about OS m>X m> is that it is built on Unim>x m>. This is where the .bash_profile comes in. When you start the Terminal app in OS m>X m> you get a bash shell by default. The bash shell comes from Unim>x m> and when it loads it runs the .bash_profile scri...