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Cannot pass null argument when using type hinting
...
362
PHP 7.1 or newer (released 2nd December 2016)
You can explicitly declare a variable to be nul...
Returning value from called function in a shell script
...ho "directory not created"
else
echo "directory already created"
fi
3. Share variable
lockdir="somedir"
retval=-1
testlock(){
if mkdir "$lockdir"
then # Directory did not exist, but it was created successfully
echo >&2 "successfully acquired lock: $lockdir"
r...
Performance of FOR vs FOREACH in PHP
...rotime(true) - $start, " Seconds\n";
And the results:
Completed in 0.0073502063751221 Seconds
Completed in 0.0019769668579102 Seconds
Completed in 0.0011849403381348 Seconds
Completed in 0.00111985206604 Seconds
So if you're modifying the array in the loop, it's several times faster to use refe...
How to delete a character from a string using Python
...to remove the central character:
midlen = len(oldstr)/2 # //2 in python 3
newstr = oldstr[:midlen] + oldstr[midlen+1:]
You asked if strings end with a special character. No, you are thinking like a C programmer. In Python, strings are stored with their length, so any byte value, including \0,...
Combine two data frames by rows (rbind) when they have different sets of columns
...
13 Answers
13
Active
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What's the best way to parse command line arguments? [closed]
...getopt. getopt is pretty much a one-to-one mapping of the standard getopt(3) C library functions, and not very easy to use.
optparse, while being a bit more verbose, is much better structured and simpler to extend later on.
Here's a typical line to add an option to your parser:
parser.add_option...
error: passing xxx as 'this' argument of xxx discards qualifiers
...
537
The objects in the std::set are stored as const StudentT. So when you try to call getId() with ...
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
...ses to objects, so I should have added "or reference to a pointer" to the #3 as well. However, I thought this would be more confusing than helpful, since references to pointers (T*&) are rarely ever used.
The dot and arrow operators can be used to refer to static class members from an object, ev...
How to include “zero” / “0” results in COUNT aggregate?
... |
edited Feb 10 '13 at 0:09
answered Feb 10 '13 at 0:04
...
Run javascript function when user finishes typing instead of on key up?
...|
edited Jul 16 '15 at 20:32
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