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What is the performance cost of having a virtual method in a C++ class?
...3ghz in-order PowerPC processor. On that architecture, a virtual function call costs 7 nanoseconds longer than a direct (non-virtual) function call.
So, not really worth worrying about the cost unless the function is something like a trivial Get()/Set() accessor, in which anything other than inli...
Why are Oracle table/column/index names limited to 30 characters?
..., but there is always a case that turns up where we hit this limit - especially in naming foreign keys.
10 Answers
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How to solve PHP error 'Notice: Array to string conversion in…'
...n $_POST['C']. So when you echo that, you are trying to print an array, so all it does is print Array and a notice.
To print properly an array, you either loop through it and echo each element, or you can use print_r.
Alternatively, if you don't know if it's an array or a string or whatever, you c...
Namespace not recognized (even though it is there)
... page.
This is a problem in Visual Studio (I would even go so far as to call it a bug). AutoMapper requires assemblies that are excluded from the .NET Framework 4 Client Profile. Since your project is using that version of the framework it breaks.
A similar error will propagate to the build pro...
How to duplicate sys.stdout to a log file?
...est way to accomplish logging when a python app is making a lot of system calls?
17 Answers
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How to replace master branch in Git, entirely, from another branch? [duplicate]
...aster
git merge seotweaks
The result should be your master is now essentially seotweaks.
(-s ours is short for --strategy=ours)
From the docs about the 'ours' strategy:
This resolves any number of heads, but the resulting tree of the merge is always that of the current branch head, effecti...
How to remove all whitespace from a string?
...\r\v\fy \t\n\r\v\f"
## [4] NA
The base R approach: gsub
gsub replaces all instances of a string (fixed = TRUE) or regular expression (fixed = FALSE, the default) with another string. To remove all spaces, use:
gsub(" ", "", x, fixed = TRUE)
## [1] "xy" "←→" ...
Nested defaultdict of defaultdict
Is there a way to make a defaultdict also be the default for the defaultdict? (i.e. infinite-level recursive defaultdict?)
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How can I format my grep output to show line numbers at the end of the line, and also the hit count?
... sometimes man page can take many pages. And this is hard to read all of them
– Eugen Konkov
May 22 '18 at 13:44
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sprintf like functionality in Python
...uld like to create a string buffer to do lots of processing, format and finally write the buffer in a text file using a C-style sprintf functionality in Python. Because of conditional statements, I can’t write them directly to the file.
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