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How do I get a PHP class constructor to call its parent's parent's constructor?
I need to have a class constructor in PHP call its parent's parent's (grandparent?) constructor without calling the parent constructor.
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Getting SyntaxError for print with keyword argument end=' '
...print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for ...
Regular expression to find URLs within a string
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It's 2017, and unicode domain names are all over the place. \w may not match international symbols (depends on regex engine), the range is needed instead: a-zA-Z0-9\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF.
– Michael Antipin
Aug...
How to convert a Django QuerySet to a list
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Why not just call list() on the Queryset?
answers_list = list(answers)
This will also evaluate the QuerySet/run the query. You can then remove/add from that list.
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git ignore vim temporary files
...t is the correct way to make git ignore temporary files produced by vim in all directories (either globally across the system or locally for a single project)?
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Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...
Can comments be used in JSON?
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No.
The JSON should all be data, and if you include a comment, then it will be data too.
You could have a designated data element called "_comment" (or something) that would be ignored by apps that use the JSON data.
You would probably be bett...
What is the instanceof operator in JavaScript?
...ce p inherits from Person.prototype.
Per the OP's request
I've added a small example with some sample code and an explanation.
When you declare a variable you give it a specific type.
For instance:
int i;
float f;
Customer c;
The above show you some variables, namely i, f, and c. The type...
Check if object is file-like in Python
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It is generally not good practice to have checks like this in your code at all unless you have special requirements.
In Python the typing is dynamic, why do you feel need to check whether the object is file like, rather than just usin...
Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell
... and the time changes to 11.1 seconds
in factorCount' you have needlessly called fromIntegral. A fix results in no change though (the compiler is smart, lucky for you).
You used mod where rem is faster and sufficient. This changes the time to 8.5 seconds.
factorCount' is constantly applying two extr...