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Why cannot cast Integer to String in java?
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Why this is not possible:
Because String and Integer are not in the same Object hierarchy.
Object
/ \
/ \
String Integer
The casting which you are trying, works only if they are in the same hierarchy, e.g.
Object
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Is there a C# case insensitive equals operator?
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Try this:
string.Equals(a, b, StringComparison.CurrentCultureIgnoreCase);
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How do I return early from a rake task?
... an exit code of 1) you'll want to use abort, which also takes an optional string param that will get outputted on exit:
task :check do
# If any of your checks fail, you can exit early like this.
abort( "One of the checks has failed!" ) if check_failed?
end
On the command line:
$ rake che...
How to get JQuery.trigger('click'); to initiate a mouse click
... if one of the hrefs on the <a tag is '#', that would do it. <a normally redirects to a different URL. You must stop it with ev.preventDefault() and ev.stopPropagation() before your click handler returns. OR, use some other tag besides <a; you can attach click handlers to anything that's...
Equivalent of varchar(max) in MySQL?
... but a varchar also includes a byte or two to encode the length of a given string. So you actually can't declare a varchar of the maximum row size, even if it's the only column in the table.
mysql> CREATE TABLE foo ( v VARCHAR(65534) );
ERROR 1118 (42000): Row size too large. The maximum row siz...
What is the 'dynamic' type in C# 4.0 used for?
...= foo / 2.5; // Does not compile
foo = Math.Sqrt(foo); // Does not compile
string bar = foo.ToString("c");
The second line does not compile because 2.5 is typed as a double and line 3 does not compile because Math.Sqrt expects a double. Obviously, all you have to do is cast and/or change your vari...
What does “Object reference not set to an instance of an object” mean? [duplicate]
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The following code is a simple way of reproducing this:
static void Main(string[] args)
{
var exampleClass = new ExampleClass();
var returnedClass = exampleClass.ExampleMethod();
returnedClass.AnotherExampleMethod(); //NullReferenceException here.
}
class ExampleClass
{
public Ret...
What are the differences between struct and class in C++?
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That's not really a second difference, it's just that the question stated the difference incompletely. All subobjects are private by default when using the class, public by default with struct, and both define a class type.
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When should I choose Vector in Scala?
It seems that Vector was late to the Scala collections party, and all the influential blog posts had already left.
6 Answ...
SQL query to get all values a enum can have
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The unnest call will return records of type myenum with a column name of "myenum". You might also want to cast the enum to text and specify a column name by adding something like. ::text AS my_column
– Justin Oh...