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`from … import` vs `import .` [duplicate]
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I just tried import urllib.request and it doesn't work at all (python 2.6.5 Ubuntu).
– tkone
Feb 24 '12 at 23:33
6
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JavaScript listener, “keypress” doesn't detect backspace?
...s invoked only for character (printable) keys, KeyDown event is raised for all including nonprintable such as Control, Shift, Alt, BackSpace, etc.
UPDATE:
The keypress event is fired when a key is pressed down and that key normally produces a character value
Reference.
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Get the client IP address using PHP [duplicate]
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I usually don't like nested ternaries, but I really like it in this case...
– Charles Harmon
Jul 18 '14 at 20:49
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How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
I've been digging through some parts of the Linux kernel, and found calls like this:
10 Answers
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Chrome sendrequest error: TypeError: Converting circular structure to JSON
...mit": null,
"size": 0,
"chunks": [],
"writable": true,
"readable": false,
"_events": {
"pipe": [null, null],
"error": [null]
},
"before": [null],
"after": [],
"response": {
"output": [],
"outputEncodings": [],
"writable": true,
"_last": false,
"chunkedEncoding": false,
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How to get the parents of a Python class?
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If you want all the ancestors rather than just the immediate ones, use inspect.getmro:
import inspect
print inspect.getmro(cls)
Usefully, this gives you all ancestor classes in the "method resolution order" -- i.e. the order in which ...
Private and Protected Members : C++
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Public members of a class A are accessible for all and everyone.
Protected members of a class A are not accessible outside of A's code, but is accessible from the code of any class derived from A.
Private members of a class A are not accessible outside of A's code, or f...
Windows batch: formatted date into variable
...nswered May 20 '14 at 8:59
richhallstokerichhallstoke
1,30111 gold badge1414 silver badges2525 bronze badges
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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
C++ preprocessor __VA_ARGS__ number of arguments
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This is actually compiler dependent, and not supported by any standard.
Here however you have a macro implementation that does the count:
#define PP_NARG(...) \
PP_NARG_(__VA_ARGS__,PP_RSEQ_N())
#define PP_NARG_(...) \
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