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Unable to Cast from Parent Class to Child Class
...Employee
Employee e = (Employee)p; // Casting allowed
Conclusion : After reading above all, hope it will make sense now like how parent to child conversion is possible(Case 3).
Answer To The Question :
Your answer is
in case 2.Where you can see such casting is not allowed by OOP and yo...
The best way to remove duplicate values from NSMutableArray in Objective-C?
...ed to make a copy of the entire array), and is in my opinion a little more readable.
Note that in either case, checking to see if an item is already included in the target array (using containsObject: in my example, or indexOfObject:inRange: in Jim's) doesn't scale well for large arrays. Those chec...
Convert PHP closing tag into comment
...
Why use complicated, difficult to read "tricks" to work around the problem?
? is just a quantifier shortcut for convenience, so
Just use the long version of the quantifier {0,1}, means "minimum 0 maximum 1 occurrence":
$string = preg_replace('#<br\s*/{0...
How to create a directory if it doesn't exist using Node.js?
...ory if it doesn't exist.
It should have full permission for the script and readable by others.
17 Answers
...
Check to see if python script is running
...pidfile = "/tmp/mydaemon.pid"
if os.path.isfile(pidfile):
print "%s already exists, exiting" % pidfile
sys.exit()
file(pidfile, 'w').write(pid)
try:
# Do some actual work here
finally:
os.unlink(pidfile)
Then you can check to see if the process is running by checking to see if the...
How do I calculate percentiles with python/numpy?
... list of values.
@parameter N - is a list of values. Note N MUST BE already sorted.
@parameter percent - a float value from 0.0 to 1.0.
@parameter key - optional key function to compute value from each element of N.
@return - the percentile of the values
"""
if not N:
...
The specified named connection is either not found in the configuration, not intended to be used wit
...string data should exist in the config file of the project that the .Net threads initiated from by CLR (i.e. your startup project).
If this is not your case, then just open your edmx file, right click on its surface, select properties and copy the connection string and paste it into your app.config ...
What did MongoDB not being ACID compliant before v4 really mean?
...ment is
Atomic: it either fully completes or it does not
Consistent: no reader will see a "partially applied" update
Isolated: again, no reader will see a "dirty" read
Durable: (with the appropriate write concern)
What MongoDB doesn't have is transactions -- that is, multiple-document updates ...
How to disable Google Chrome auto update?
...
Have spent a long time trying to disable updates (literally hours, reading forums and testing various (some exotic) solutions), and this was driving me crazy. But there what seems an infallible solution (see further down).
Even using the official Google page with the templates did NOTHING: ...
Set a DateTime database field to “Now”
...
This is quite wrong. I just read the docs on those two and it appears obvious to me that those aren't "exact the same thing". This question offers a more detailed explanation for this: stackoverflow.com/questions/7105093/…
– Mlad...