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Rails: Why does find(id) raise an exception in rails? [duplicate]
...ctiveRecord, the default behaviour is to return nil or false for failures, and leave the exception control flow to methods ending in a bang (#save!).
– Marten Veldthuis
Aug 12 '11 at 8:07
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How to remove all white spaces in java [duplicate]
I have a programming assignment and part of it requires me to make code that reads a line from the user and removes all the white space within that line.
the line can consist of one word or more.
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How do I calculate a point on a circle’s circumference?
... r * cos(a)
y = cy + r * sin(a)
Where r is the radius, cx,cy the origin, and a the angle.
That's pretty easy to adapt into any language with basic trig functions. Note that most languages will use radians for the angle in trig functions, so rather than cycling through 0..360 degrees, you're cycli...
What is the difference between using IDisposable vs a destructor in C#?
...d a finalizer (destructor) the GC has to call it (even an empty finalizer) and to call it the object will always survive a gen 1 garbage collect. This will impede and slow down the GC. That's wht Marc says to call SuppressFinalize in the above code
– Kevin Jones
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enum - getting value of enum on string conversion
...at:
print(D.x.value)
See the Programmatic access to enumeration members and their attributes section:
If you have an enum member and need its name or value:
>>>
>>> member = Color.red
>>> member.name
'red'
>>> member.value
1
You could add a __str__ meth...
Convert to absolute value in Objective-C
...s(double), or fabsl(long double).
Those functions are all part of the C standard library, and so are present both in Objective-C and plain C (and are generally available in C++ programs too.)
(Alas, there is no habs(short) function. Or scabs(signed char) for that matter...)
Apple's and GNU's Ob...
Python's os.makedirs doesn't understand “~” in my path
...
You need to expand the tilde manually:
my_dir = os.path.expanduser('~/some_dir')
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Thread.Sleep replacement in .NET for Windows Store
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Windows Store apps embrace asynchrony - and an "asynchronous pause" is provided by Task.Delay. So within an asynchronous method, you'd write:
await Task.Delay(TimeSpan.FromSeconds(30));
... or whatever delay you want. The asynchronous method will continue 30 sec...
Is it possible to change the radio button icon in an android radio button group
I am wanting to allow the user of my android application the ability to set some parameters. The radio button is ideal for this situation. However, I don't like the radio buttons are rendered.
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Credit card expiration dates - Inclusive or exclusive?
...u ever wanted to know about credit cards.
This is assumed to be a typo and that it should read "..., after the first day of the next month; ..."
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