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How do I find out if first character of a string is a number?
In Java is there a way to find out if first character of a string is a number?
5 Answers
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Is it a bad practice to use break in a for loop? [closed]
...dangers" associated with using break or continue in a for loop are negated if you write tidy, easily-readable loops. If the body of your loop spans several screen lengths and has multiple nested sub-blocks, yes, you could easily forget that some code won't be executed after the break. If, however, t...
Rails :dependent => :destroy VS :dependent => :delete_all
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The difference is with the callback.
The :delete_all is made directly in your application and deletes by SQL :
DELETE * FROM users where compagny_id = XXXX
With the :destroy, there is an instantiation of all of your children. ...
How to determine an object's class?
If class B and class C extend class A and I have an object of type B or C , how can I determine of which type it is an instance?
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Returning from a finally block in Java
...you provided are reason enough to not use flow-control from finally.
Even if there's a contrived example where it's "better," consider the developer who has to maintain your code later and who might not be aware of the subtleties. That poor developer might even be you....
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Build a Basic Python Iterator
...next__(self): # Python 2: def next(self)
self.current += 1
if self.current < self.high:
return self.current
raise StopIteration
for c in Counter(3, 9):
print(c)
This will print:
3
4
5
6
7
8
This is easier to write using a generator, as covered in a p...
How do I change the value of a global variable inside of a function
... reference the variable inside the function; no magic, just use it's name. If it's been created globally, then you'll be updating the global variable.
You can override this behaviour by declaring it locally using var, but if you don't use var, then a variable name used in a function will be global ...
'dragleave' of parent element fires when dragging over children elements
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If you don't need to bind events to the child elements, you can always use the pointer-events property.
.child-elements {
pointer-events: none;
}
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`static` keyword inside function?
...$has_run in your example) between multiple calls.
You could use this for different purposes, for example:
function doStuff() {
static $cache = null;
if ($cache === null) {
$cache = '%heavy database stuff or something%';
}
// code using $cache
}
In this example, the if would only b...
How to change variables value while debugging with LLDB in Xcode?
...alue while debugging in XCode? ). Does LLDB offer a similar functionality? If so, how can we use it?
3 Answers
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