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How are Python's Built In Dictionaries Implemented?
...thon in Python 3.6. Ordering by insertion was considered an implementation detail for 3.6 to allow other implementations of Python a chance to catch up.
Shared Keys
Another optimization to save space is an implementation that shares keys. Thus, instead of having redundant dictionaries that take up...
How to debug Lock wait timeout exceeded on MySQL?
... to finish
(see the last two paragraph below to specify the terms in more detail)
=> deadlock
This is a very unfortunate setup because MySQL cannot see there is a deadlock (spanned within 3 transactions). So what MySQL does is ... nothing! It just waits, since it does not know what to do. It...
Explaining Python's '__enter__' and '__exit__'
...ocs.python.org/3/reference/datamodel.html#with-statement-context-managers
(detail is the same for both versions)
object.__enter__(self)
Enter the runtime context related to this object. The with statement will bind this method’s return value to the target(s) specified in the as clause of the...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...
The implementation details of pow are neither here nor there; this answer doesn't even reference pow.
– Stephen Canon
Jan 3 '13 at 2:19
...
Java: difference between strong/soft/weak/phantom reference
...e you the referrant). I'd suggest you reading this article to get in-depth detail about this.
So you can say that, strong references have ultimate power (can never be collected by GC)
Soft references are powerful than weak references (as they can escape GC cycle until JVM runs out of memory)
Weak r...
Wrap a delegate in an IEqualityComparer
... include a GetHashCode method; but nobody's bothered to explain why in any detail.
Here's why. Your question specifically mentions the LINQ extension methods; nearly all of these rely on hash codes to work properly, because they utilize hash tables internally for efficiency.
Take Distinct, for exa...
What is Rack middleware?
...ine doing:
Authentication: when the request arrives, are the users logon details correct? How do I validate this OAuth, HTTP Basic Authentication, name/password?
Authorisation: "is the user authorised to perform this particular task?", i.e. role-based security.
Caching: have I processed this reque...
What is the difference between loose coupling and tight coupling in the object oriented paradigm?
... you have "loose coupling". See below for elaboration.
Tight coupling (Detailed Example)
Think of your skin. It's stuck to your body. It fits like a glove. But what if you wanted to change your skin colour from say white to green? Can you imagine just how painful it would be to peel off your sk...
Best practices for exception management in Java or C# [closed]
...
@Trejkaz You don't want to return the exception detail to users, because that is a security risk. This is why HTML servers return error codes. It's also a localization issue to return an error message, and probably makes the HTML bigger in size and slower to return. All th...
Best Practice for Exception Handling in a Windows Forms Application?
...e to be able to handle error conditions then create custom exceptions that detail what the un excepected situation is and provide relevant information. Otherwise just stick to built-in exception types as much as possible.
s...