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Passing a single item as IEnumerable
...f you pass in a list or an array, then an unscrupulous piece of code could cast it and change the contents, leading to odd behaviour in some situations. You could use a read-only collection, but that's likely to involve even more wrapping. I think your solution is as neat as it gets.
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Is there a Python equivalent to Ruby's string interpolation?
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@Caste see here: docs.python.org/library/stdtypes.html#string-formatting and post a follow up comment if you need any more details
– mikej
Dec 15 '10 at 13:59
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Cannot create an array of LinkedLists in Java…?
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For some reason you have to cast the type and make the declaration like this:
myMatrix = (LinkedList<IntegerNode>[]) new LinkedList<?>[numRows];
share
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How to do ToString for a possibly null object?
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C# 6.0 Edit:
With C# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "")....
What is a raw type and why shouldn't we use it?
... String name = (String) o;
System.out.println(name);
} // throws ClassCastException!
// java.lang.Boolean cannot be cast to java.lang.String
Now we run into trouble at run-time, because names contains something that isn't an instanceof String.
Presumably, if you want names to contain only...
What are POD types in C++?
...en pointers to vtables, offsets that get applied to the address when it is cast to other types (at least if the target's POD too), constructors, or destructors. Roughly speaking, a type is a POD when the only things in it are built-in types and combinations of them. The result is something that "act...
What are the differences between “generic” types in C++ and Java?
...acro). In Java they are basically syntactic sugar to minimize boilerplate casting of Objects. Here is a pretty decent introduction to C++ templates vs Java generics.
To elaborate on this point: when you use a C++ template, you're basically creating another copy of the code, just as if you used a ...
What is the list of valid @SuppressWarnings warning names in Java?
...ngs
boxing to suppress warnings relative to boxing/unboxing operations
cast to suppress warnings relative to cast operations
dep-ann to suppress warnings relative to deprecated annotation
deprecation to suppress warnings relative to deprecation
fallthrough to suppress warnings relative to ...
Passing data between a fragment and its container activity
...ithin YOUR Activity (and not the parent Android activity) you will need to cast your getActivity() call: ((MyActivity) getActivity()).getResult();
– Nick
Feb 21 '12 at 17:20
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How to determine an object's class?
... are still more methods: Class.isAssignableFrom() and simply attempting to cast the object (which might throw a ClassCastException).
Possible ways summarized
Let's summarize the possible ways to test if an object obj is an instance of type C:
// Method #1
if (obj instanceof C)
;
// Method #2...