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How do function pointers in C work?
...nPtr)(2, 3); // sum == 5
Passing the pointer to another function is basically the same:
int add2to3(int (*functionPtr)(int, int)) {
return (*functionPtr)(2, 3);
}
We can use function pointers in return values as well (try to keep up, it gets messy):
// this is a function called functionFac...
Interface vs Abstract Class (general OO)
...
While your question indicates it's for "general OO", it really seems to be focusing on .NET use of these terms.
In .NET (similar for Java):
interfaces can have no state or implementation
a class that implements an interface must provide an implementation of all the methods of tha...
Enterprise Library Unity vs Other IoC Containers [closed]
...em have other features as well (some have AOP, and better gizmos, but generally all I want an IOC to do is create and retrieve objects for me)
Note: the differences between the different libraries object retrieval can be negated by using the CommonServiceLocator: http://www.codeplex.com/CommonServi...
What are the Ruby Gotchas a newbie should be warned about? [closed]
I have recently learned the Ruby programming language, and all in all it is a good language. But I was quite surprised to see that it was not as simple as I had expected. More precisely, the "rule of least-surprise" did not seem very respected to me (of course this is quite subjective). For examp...
How to select rows that have current day's timestamp?
... The index is used to select the rows. But the whole index is scanned (and all values are converted with DATE() to evaluate the condition) with your query. I'll update my answer with a better example.
– ypercubeᵀᴹ
Feb 8 '13 at 12:43
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AWK: Access captured group from line pattern
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I prefer 'perl -n -p -e...' over awk for almost all use cases, since it is more flexible, more powerful and has a saner syntax in my opinion.
– Peter Tillemans
Jun 23 '11 at 18:39
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Best way to trim strings after data entry. Should I create a custom model binder?
I'm using ASP.NET MVC and I'd like all user entered string fields to be trimmed before they're inserted into the database. And since I have many data entry forms, I'm looking for an elegant way to trim all strings instead of explicitly trimming every user supplied string value. I'm interested to ...
In C#, can a class inherit from another class and an interface?
...develop a generic component/interface that I can use to write programs for all our devices that will help keep the common things (like connecting, disconnecting, getting firmware) the same for all of our applications.
...
What to do with commit made in a detached head
...ter. To avoid detached head, don't checkout old commits. If you still want all the files from there, but as a new commit, then you could checkout the directory from the commit, instead of the commit itself. See this answer
– lucidbrot
Dec 3 '17 at 10:35
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SQL: How to properly check if a record exists
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I would prefer not use Count function at all:
IF [NOT] EXISTS ( SELECT 1 FROM MyTable WHERE ... )
<do smth>
For example if you want to check if user exists before inserting it into the database the query can look like this:
IF NOT EXISTS ( SELECT 1 ...