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What is the difference between NULL, '\0' and 0?
...he value 0, it is just described in different ways.
If a pointer is being compared to the constant literal 0, then this is a check to see if the pointer is a null pointer. This 0 is then referred to as a null pointer constant. The C standard defines that 0 cast to the type void * is both a null poi...
Parse string to DateTime in C#
...exact can be useful. Sometimes, I would prefer my application crash and my computer light on fire, as opposed to producing incorrect output. Depends on the application.
– Allen
Jul 31 '15 at 18:03
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JPA : How to convert a native query result set to POJO class collection
...class was not a known Entity. I ended up using this approach stackoverflow.com/questions/5024533/… instead of trying to use a native query.
– FGreg
Jan 30 '13 at 21:43
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Difference between attr_accessor and attr_accessible
...oks like Rails4 has a new way to do things. See this answer: stackoverflow.com/questions/17371334/…
– Paul Rubel
Jan 15 '14 at 16:40
1
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What are the best use cases for Akka framework [closed]
... scala by the way)
One of the big advantages is the ease at which you can compose a system out of actors and messages with almost no boilerplating, it scales extremely well without all the complexities of hand-rolled threading and you get asynchronous message passing between objects almost for free...
How to prevent buttons from submitting forms
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Does Java have something like C#'s ref and out keywords?
...t's always clear when you're passing something by reference. yoda.arachsys.com/csharp/parameters.html
– Mark Byers
May 10 '10 at 22:03
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Fastest way to replace NAs in a large data.table
...d at NAToUnknown).
EDIT (more elegant solution as requested by Ramnath in comments) :
f_dowle2 = function(DT) {
for (i in names(DT))
DT[is.na(get(i)), (i):=0]
}
system.time(f_dowle2(dt1))
user system elapsed
6.468 0.760 7.250 # faster, too
identical(a_gdata, dt1)
[1] TRUE
I...
Can enums be subclassed to add new elements?
...have a base class called e.g. IntEnum, that looks like this: stackoverflow.com/questions/1681976/enum-with-int-value-in-java/…. Then all my enums could extend it...in this case just benefitting from inheritance and thus I wouldn't have to duplicate this "int-based enum" code frequently. I am new...
Python subprocess.Popen “OSError: [Errno 12] Cannot allocate memory”
...or because security_vm_enough_memory_mm failed you while enforcing the overcommit policy.
Start by checking the vmsize of the process that failed to fork, at the time of the fork attempt, and then compare to the amount of free memory (physical and swap) as it relates to the overcommit policy (plug ...