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what is the difference between ?:, ?! and ?= in regex?
...etween lookahead and non-capturing groups it is all about if you want just test the existence or test and save the match. Capturing group are expensive so use it judiciously.
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How do you allow spaces to be entered using scanf?
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I did not test, but based on other answers in this very page, I believe the correct buffer size for scanf in your example would be: scanf("%19[^\n]", name); (still +1 for the concise answer)
– DrBeco
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How to send a GET request from PHP?
...rom server-side caching of some resource, etc? Maybe You should repeat the test?
– Rauni Lillemets
Dec 4 '15 at 12:17
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Can I browse other people's (Apple) bug reports? [closed]
...cted by Apple twice regarding fixed bugs or getting additional feedback or testing. Still, I think that it may happen for 1:50 and only for serious bugs.
– sorin
Jan 12 '17 at 21:48
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How do I set default values for functions parameters in Matlab?
...or isempty(myParameterName)
MyParameterName = defaultValue;
elseif (.... tests for non-validity of the value actually provided ...)
error('The sky is falling!')
end
Ok, so I would generally apply a better, more descriptive error message. See that the check for an empty variable allows the user...
Status bar won't disappear
I'm creating an application and I want the status bar hidden. When I test the app, the status bar is hidden whilst the splash screen is shown, but once the app is fully loaded, the status bar reappears.
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Bitwise operation and usage
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One typical usage:
| is used to set a certain bit to 1
& is used to test or clear a certain bit
Set a bit (where n is the bit number, and 0 is the least significant bit):
unsigned char a |= (1 << n);
Clear a bit:
unsigned char b &= ~(1 << n);
Toggle a bit:
unsigned char ...
Efficient evaluation of a function at every cell of a NumPy array
Given a NumPy array A , what is the fastest/most efficient way to apply the same function, f , to every cell?
6 Ans...
How to output git log with the first line only?
...e after the first line. The command above usually works for me, but I just tested on a commit without empty second line. I got the same result as you: the whole message on one line.
Empty second line is a standard in git commit messages. The behaviour you see was probably implemented on purpose.
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How to delete from multiple tables in MySQL?
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I don't have a mysql database to test on at the moment, but have you tried specifying what to delete prior to the from clause? For example:
DELETE p, pa FROM `pets` p,
`pets_activities` pa
WHERE p.`order` > :order
AND p.`pet_id` = :pet_id
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