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What is the C# equivalent of NaN or IsNumeric?
...myNum)) {
// it is a number
} else {
// it is not a number
}
Incidentally, all of the standard data types, with the glaring exception of GUIDs, support TryParse.
update
secretwep brought up that the value "2345," will pass the above test as a number. However, if you need to ensure that all o...
Possible to do a MySQL foreign key to one of two possible tables?
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What you're describing is called Polymorphic Associations. That is, the "foreign key" column contains an id value that must exist in one of a set of target tables. Typically the target tables are related in some way, such as being instances of some c...
Why can I add named properties to an array as if it were an object?
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Virtually everything in javascript is an object, so you can "abuse" an Array object by setting arbitrary properties on it. This should be considered harmful though. Arrays are for numerically indexed data - for non-numeric keys, u...
Missing file warnings showing up after upgrade to Xcode 4
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I additionally had to quit and kill xcode for the problem to go away.
– Twilite
Apr 3 '12 at 16:31
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Why do we need extern “C”{ #include } in C++?
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C and C++ are superficially similar, but each compiles into a very different set of code. When you include a header file with a C++ compiler, the compiler is expecting C++ code. If, however, it is a C header, then the compiler expects the data cont...
Bomb dropping algorithm
...to bomb the hollow rectangle of
squares just inside the perimeter. I'll call the perimeter layer 1, and the rectangle inside it layer 2.
An important insight is that there is no point bombing layer 1, because the
"blast radius" you get from doing so is always contained within the blast radius of...
Hiding the scroll bar on an HTML page
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Actually, this is not completely the right answer : overflow:hidden doesn't "hide" the scrollbar. It also stop scrolling feature on the page. That's not exactly what we ask for.
– adriendenat
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What is the difference between Tomcat, JBoss and Glassfish?
... and CORBA. We didn't include these in the Java EE version of Tomcat, but all current technology is there like JAX-RS, JAX-WS, JMS, CDI, JPA, JSF, EJB, JTA, etc.
– David Blevins
Aug 26 '13 at 21:01
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How do I undo the most recent local commits in Git?
I accidentally committed the wrong files to Git , but I haven't pushed the commit to the server yet.
86 Answers
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What algorithm gives suggestions in a spell checker?
What algorithm is typically used when implementing a spell checker that is accompanied with word suggestions?
5 Answers
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