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Meaning of $? (dollar question mark) in shell scripts
.../drush status bootstrap | grep -q $(vendor/bin/drush php-eval 'if (function_exists("t")) echo t("Successful");') &> /dev/null;. If I had to put that in a single line if [ ... ] it would be terribly unreadable. I plan to store the output of that line to a variable so I can just say if [ $drupa...
How do I declare a 2d array in C++ using new?
...
A dynamic 2D array is basically an array of pointers to arrays. You can initialize it using a loop, like this:
int** a = new int*[rowCount];
for(int i = 0; i < rowCount; ++i)
a[i] = new int[colCount];
The above, for colCount= 5 and rowCount =...
What is the difference between map and flatMap and a good use case for each?
...ark-shell session:
First, some data - two lines of text:
val rdd = sc.parallelize(Seq("Roses are red", "Violets are blue")) // lines
rdd.collect
res0: Array[String] = Array("Roses are red", "Violets are blue")
Now, map transforms an RDD of length N into another RDD of length N.
For examp...
Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
What does functools.wraps do?
... def with_logging(*args, **kwargs):
print(func.__name__ + " was called")
return func(*args, **kwargs)
return with_logging
then when you say
@logged
def f(x):
"""does some math"""
return x + x * x
it's exactly the same as saying
def f(x):
"""does some math"""
...
What are libtool's .la file for?
... # Static library
/lib/libfoo.la # libtool library
/bin/cygfoo_1.dll # DLL
Under Windows MinGW:
/lib/libfoo.dll.a # Import library
/lib/libfoo.a # Static library
/lib/libfoo.la # 'libtool' library
/bin/foo_1.dll # DLL
So libfoo.la is the only file that is p...
HTTP Basic Authentication - what's the expected web browser experience?
When a server allows access via Basic HTTP Authentication, what is the experience expected to be in a web browser ?
6 Answ...
What is the best django model field to use to represent a US dollar amount?
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I think this example is correct almost to all currencies. To represent currencies as Bitcoin, I think is much better to use an integer field to save the amount in satoshis, and then show it to the final user in the representation that you want (BTC, mBTC, etc)
...
Signed to unsigned conversion in C - is it always safe?
...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.
Otherwise, both operands are converted t...
What is the exact meaning of Git Bash?
... , fetch , and merge . But I still don't know what Git Bash itself actually is!
4 Answers
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