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How do I check whether a file exists without exceptions?
How do I check if a file exists or not, without using the try statement?
39 Answers
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nil detection in Go
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The compiler is pointing the error to you, you're comparing a structure instance and nil. They're not of the same type so it considers it as an invalid comparison and yells at you.
What you want to do here is to compare a pointer to your config instance to...
REST HTTP status codes for failed validation or invalid duplicate
...ST-based API and have come to the point where i'm specifying status codes for each requests.
9 Answers
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How can I pass a list as a command-line argument with argparse?
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TL;DR
Use the nargs option or the 'append' setting of the action option (depending on how you want the user interface to behave).
nargs
parser.add_argument('-l','--list', nargs='+', help='<Required> Set flag', required=True)
# Use like:
# pytho...
Why do I have to access template base class members through the this pointer?
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Short answer: in order to make x a dependent name, so that lookup is deferred until the template parameter is known.
Long answer: when a compiler sees a template, it is supposed to perform certain checks immediately, without s...
What is console.log?
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It's not a jQuery feature but a feature for debugging purposes. You can for instance log something to the console when something happens. For instance:
$('#someButton').click(function() {
console.log('#someButton was clicked');
// do something
});
You'd then ...
EJB's - when to use Remote and/or local interfaces?
... a remote call, using RMI semantics and all the overhead it implies (a network call and object serialization for every method call). EJB clients had to pay this performance penalty even when collocated in the same virtual machine with the EJB container.
Later, Sun realized most business applicatio...
Best way to convert IList or IEnumerable to Array
I have a HQL query that can generate either an IList of results, or an IEnumerable of results.
4 Answers
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iPad/iPhone hover problem causes the user to double click a link
...nd i noticed that all the mouse over events are translated in clicks...so for instance i have to do two clicks instead of one..(the first hover, than the actual click)
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Why do we use __init__ in Python classes?
...__init__ doesn't initialize a class, it initializes an instance of a class or an object. Each dog has colour, but dogs as a class don't. Each dog has four or fewer feet, but the class of dogs doesn't. The class is a concept of an object. When you see Fido and Spot, you recognise their similarity, th...