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Finding the index of an item in a list
... complete. Some caveats about list.index follow. It is probably worth initially taking a look at the documentation for it:
list.index(x[, start[, end]])
Return zero-based index in the list of the first item whose value is equal to x. Raises a ValueError if there is no such item.
The optional argum...
Clear back stack using fragments
...tBackStackEntryCount(); ++i) {
fm.popBackStack();
}
But could equally have used something like:
((AppCompatActivity)getContext()).getSupportFragmentManager().popBackStack(String name, FragmentManager.POP_BACK_STACK_INCLUSIVE)
Which will pop all states up to the named one. You can then j...
Which is more preferable to use: lambda functions or nested functions ('def')?
...nction objects, but list comprehensions and generator expressions are generally more readable than those functions and can cover all use cases, without the need of lambdas.
For the cases you really need a small function object, you should use the operator module functions, like operator.add instea...
Javascript “this” pointer within nested function
...
In JavaScript the this object is really based on how you make your function calls.
In general there are three ways to setup the this object:
someThing.someFunction(arg1, arg2, argN)
someFunction.call(someThing, arg1, arg2, argN)
someFunction.apply(someThing...
Is it safe to parse a /proc/ file?
.../proc/mounts was a consistent snapshot.
For example:
/proc/uptime is totally atomic, as someone mentioned in another answer -- but only since Linux 2.6.30, which is less than two years old. So even this tiny, trivial file was subject to a race condition until then, and still is in most enterpris...
__getattr__ on a module
...
A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__...
Passing argument to alias in bash [duplicate]
...etom: If you're referring to the colors in my answer, that's done automatically by the syntax highlighter.
– Paused until further notice.
Jul 7 '14 at 5:12
...
What is the advantage of GCC's __builtin_expect in if else statements?
...
I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
...
after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...
Python multiprocessing PicklingError: Can't pickle
...the one you posted:
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__args, **self.__kwargs)
File "/usr/lib/p...
How to achieve function overloading in C?
...sociation list that looks a bit like a switch block. _Generic gets the overall type of the expression and then "switches" on it to select the end result expression in the list for its type:
_Generic(1, float: 2.0,
char *: "2",
int: 2,
default: get_two_object());
...