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Does Python optimize tail recursion?
...ons.
The clean way: modifying the Y combinator
The Y combinator is well known; it allows to use lambda functions in a recursive
manner, but it doesn't allow by itself to embed recursive calls in a loop. Lambda
calculus alone can't do such a thing. A slight change in the Y combinator however
can pr...
Null coalescing in powershell
... evaluated
Null Conditional Assignment
$x = $null
$x ??= 100 # $x is now 100
$x ??= 200 # $x remains 100
Ternary Operator
$true ? "this value returned" : "this expression not evaluated"
$false ? "this expression not evaluated" : "this value returned"
Previous Versions:
No need for ...
Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
...yper-V and Windows Hypervisor Platform options and restart your system.
Now, you can Start HAXM installation without any error.
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How can I get rid of an “unused variable” warning in Xcode?
... mark variable as used is… to use it.
BOOL saved = ...;
(void)saved; // now used
You may be happy with already described compiler-specific extensions, though.
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`from … import` vs `import .` [duplicate]
...e.
This makes all names from the module available in the local namespace.
Now let's see what happens when we do import X.Y:
>>> import sys
>>> import os.path
Check sys.modules with name os and os.path:
>>> sys.modules['os']
<module 'os' from '/System/Library/Framework...
Getting realtime output using subprocess
...ut.readline()
if not line: break
...
does not. Apparently this is a known bug: http://bugs.python.org/issue3907 (The issue is now "Closed" as of Aug 29, 2018)
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Will the base class constructor be automatically called?
...tion and calls. In your Base class with a non-default constructor you must now either call that constructor explicitly from the derived class or add a default constructor explicitly in the base class.
Let's test this.....
// THIS WORKS!!!
class MyBaseClass0
{
// no default constructor - create...
mysql_config not found when installing mysqldb python interface
...oo on openSUSE, where "libmysqlclient-dev" becomes "libmysqlclient-devel". Now the pip package installs fine. Thanks.
– pbarill
Nov 30 '13 at 4:14
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How to identify numpy types in python?
...umpyish, add an or to test for that. And so on. The point is, you have to know what you're actually asking for when you want to do something as unusual as loose manual type switching, but once you know, it's easy to implement.
– abarnert
Mar 11 '16 at 20:41
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How do you test functions and closures for equality?
...as kind of devastating because I had been storing closures in an Array and now can't remove them with indexOf({$0 == closure} so I have to refactor. IMHO optimization shouldn't influence language design, so without a quick fix like the now deprecated @objc_block in matt's answer, I would argue that...