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multiprocessing.Pool: When to use apply, apply_async or map?
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Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:
apply(f,args,kwargs)
apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,
f(*args,**kwargs)
is preferred. The...
Do I need to explicitly call the base virtual destructor?
...the destructor again as virtual on the inheriting class, but do I need to call the base destructor?
7 Answers
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PHP equivalent of .NET/Java's toString()
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@MarkAmery He gave an answer that implicitly calls the __toString() "Magic Method", but didn't mention that at all. The user asked for an answer that was like the Java toString() method, and in PHP, that's the __toString() function.
– Supuhstar
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Compare object instances for equality by their attributes
...s:
>>> x == y
True
Note that implementing __eq__ will automatically make instances of your class unhashable, which means they can't be stored in sets and dicts. If you're not modelling an immutable type (i.e. if the attributes foo and bar may change value within the lifetime of your obje...
Does Python have a string 'contains' substring method?
...methods to make in available to your custom type.
– BallpointBen
Aug 17 '18 at 7:02
31
Just make ...
Error handling in Bash
...kens code's predictability and portability).
You can either let the trap call error for you (in which case it uses the default exit code of 1 and no message) or call it yourself and provide explicit values; for instance:
error ${LINENO} "the foobar failed" 2
will exit with status 2, and give an ...
Why are all fields in an interface implicitly static and final?
I am just trying to understand why all fields defined in an Interface are implicitly static and final . The idea of keeping fields static makes sense to me as you can't have objects of an interface but why they are final (implicitly)?
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How to include external Python code to use in other files?
...ods in a file, is there a way to include those files in another file, but call them without any prefix (i.e. file prefix)?
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Regular expression for letters, numbers and - _
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To actually cover your pattern, i.e, valid file names according to your rules, I think that you need a little more. Note this doesn't match legal file names from a system perspective. That would be system dependent and more libera...
GET URL parameter in PHP
...perglobal: a built-in variable that's populated by PHP and is available in all scopes (you can use it from inside a function without the global keyword).
Since the variable might not exist, you could (and should) ensure your code does not trigger notices with:
<?php
if (isset($_GET['link'])) {
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