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Copy file or directories recursively in Python

... I suggest you first call shutil.copytree, and if an exception is thrown, then retry with shutil.copy. import shutil, errno def copyanything(src, dst): try: shutil.copytree(src, dst) except OSError as exc: # python >2.5 ...
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Selecting a row of pandas series/dataframe by integer index

... edited Jun 5 '18 at 12:40 marc_aragones 3,37644 gold badges2323 silver badges3333 bronze badges answered Apr 19 '13 at 12:20 ...
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How to check if a URL is valid

...s a URL, use: url =~ /\A#{URI::regexp}\z/ If you only want to check for web URLs (http or https), use this: url =~ /\A#{URI::regexp(['http', 'https'])}\z/ share | improve this answer |...
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In Functional Programming, what is a functor?

...e reading various articles on functional programming, but the authors typically assume the reader already understands the term. Looking around on the web has provided either excessively technical descriptions (see the Wikipedia article ) or incredibly vague descriptions (see the section on Functors...
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How do I make a textbox that only accepts numbers?

... with this two event handlers on a standard TextBox: private void textBox1_KeyPress(object sender, KeyPressEventArgs e) { if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) && (e.KeyChar != '.')) { e.Handled = true; } // only allow one de...
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Cannot run Eclipse; JVM terminated. Exit code=13

... Okey, I solve it. I just reinstall JDK 64-bit, re-extact eclipse-64bit and edit eclipse.ini again. – Prince OfThief Feb 9 '11 at 14:13 ...
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How do you create different variable names while in a loop? [duplicate]

...can do this is with exec(). For example: for k in range(5): exec(f'cat_{k} = k*2') >>> print(cat_0) 0 >>> print(cat_1) 2 >>> print(cat_2) 4 >>> print(cat_3) 6 >>> print(cat_4) 8 Here I am taking advantage of the handy f string formatting in Pytho...
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Co-variant array conversion from x to y may cause run-time exception

...js[0] = new Foo(); // again legal, with runtime exception In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
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How to find out where a function is defined?

... @EHerman I don't think you can find callers of a function with reflection. If you could it probably wouldn't work well for this because PHP files tend to be included on demand, and so you would likely not have all the code loaded which does call the function. ...
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C# pattern to prevent an event handler hooked twice [duplicate]

...ution and the best one (considering performance) is: private EventHandler _foo; public event EventHandler Foo { add { _foo -= value; _foo += value; } remove { _foo -= value; } } No Linq using required. No need to check for null before cancelling a subscrip...