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IF… OR IF… in a windows batch file
Is there a way to write an IF OR IF conditional statement in a windows batch-file?
14 Answers
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How to return a part of an array in Ruby?
...very similar array-slicing syntax to Python. Here is the ri documentation for the array index method:
--------------------------------------------------------------- Array#[]
array[index] -> obj or nil
array[start, length] -> an_array or nil
array[ran...
How do I check if an integer is even or odd? [closed]
How can I check if a given number is even or odd in C?
31 Answers
31
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Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...parameter of exit should qualify if the execution of the program went good or bad. It's a sort of heredity from older programming languages where it's useful to know if something went wrong and what went wrong.
Exit code is
0 when execution went fine;
1, -1, whatever != 0 when some error occurred...
How to set or change the default Java (JDK) version on OS X?
...tents/Home
Pick the version you want to be the default (1.6.0_65-b14-462 for arguments sake) then:
export JAVA_HOME=`/usr/libexec/java_home -v 1.6.0_65-b14-462`
or you can specify just the major version, like:
export JAVA_HOME=`/usr/libexec/java_home -v 1.8`
Now when you run java -version you wil...
PUT vs. POST in REST
According to the HTTP/1.1 Spec:
34 Answers
34
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Base64 length calculation?
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Each character is used to represent 6 bits (log2(64) = 6).
Therefore 4 chars are used to represent 4 * 6 = 24 bits = 3 bytes.
So you need 4*(n/3) chars to represent n bytes, and this needs to be rounded up to a multiple of 4.
The number of unused padding chars resulting from the roundin...
Why do we need tuples in Python (or any immutable data type)?
I've read several python tutorials (Dive Into Python, for one), and the language reference on Python.org - I don't see why the language needs tuples.
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Python: try statement in a single line
...variables to something. If they might not get set, set them to None first (or 0 or '' or something if it is more applicable.)
If you do assign all the names you are interested in first, you do have options.
The best option is an if statement.
c = None
b = [1, 2]
if c is None:
a = b
else:...
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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