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Design by contract using assertions or exceptions? [closed]
...ies, right? The two most prominent ways to do these checks are by assert and by exception .
14 Answers
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Running PostgreSQL in memory only
...y for this particular question: It's a bad idea to mix with valuable data (and thanks for the warning). For unit-testing with a dedicated DB cluster, a ramdisk is fine.
– Erwin Brandstetter
Jul 12 '15 at 0:32
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Creating an Android trial application that expires after a fixed time period
... run the app save the date/time to a file, database, or shared preferences and every time you run the app after that check to see if the trial period has ended. This is easy to circumvent because uninstalling and reinstalling will allow the user to have another trial period.
The second approach is...
Why can't enum's constructor access static fields?
Why can't enum's constructor access static fields and methods? This is perfectly valid with a class, but is not allowed with an enum.
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scala vs java, performance and memory? [closed]
I am keen to look into Scala, and have one basic question I cant seem to find an answer to:
in general, is there a difference in performance and usage of memory between Scala and Java?
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Is it possible to do start iterating from an element other than the first using foreach?
...kips however many you specify starting at the current index. On the other hand, if you wanted to use only the first three you would use .Take:
foreach (string curString in myCollection.Take(3))
These can even be paired together, so if you only wanted the 4-6 items you could do:
foreach (string c...
Why should Java ThreadLocal variables be static
... avoid any static fields in your class - make the class itself a singleton and then you can safely use the an instance level ThreadLocal as long as you have that singleton available globally.
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postgresql COUNT(DISTINCT …) very slow
...ount int not null), using triggers. But your write performance will suffer and if you update multiple x values in single transaction then you'd need to do this in some explicit order to avoid possible deadlock.
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How do I print the type of a variable in Rust?
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If you merely wish to find out the type of a variable and are willing to do it at compile time, you can cause an error and get the compiler to pick it up.
For example, set the variable to a type which doesn't work:
let mut my_number: () = 32.90;
// let () = x; would work too
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Is there a generator version of `string.split()` in Python?
...offset parameter of the str.find() method. This avoids lots of memory use, and relying on the overhead of a regexp when it's not needed.
[edit 2016-8-2: updated this to optionally support regex separators]
def isplit(source, sep=None, regex=False):
"""
generator version of str.split()
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