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Why don't structs support inheritance?
...i)
values [i].A *= 2;
}
Derived[] v = new Derived[2];
Square (v);
By normal conversion rules, a Derived[] is convertible to a Base[] (for better or worse), so if you s/struct/class/g for the above example, it'll compile and run as expected, with no problems. But if Base and Derived are valu...
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...l#Indexing
R has three basic indexing operators, with syntax displayed by the following examples
x[i]
x[i, j]
x[[i]]
x[[i, j]]
x$a
x$"a"
For vectors and matrices the [[ forms are rarely used, although they have some slight semantic differences from the [ form (e.g. it...
“Wrong type argument: commandp” error when binding a lambda to a key
...active command. (lambda () (interactive) (forward-line 5)) ought to work.
By the way, C-h f commandp is a pretty good starting point for errors like that.
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Patterns for handling batch operations in REST web services?
...ut that updating several attributes on a single resource is nicely covered by PATCH - no need for creativity in this case.
– LB2
Dec 2 '16 at 16:17
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C++ mark as deprecated
...t describes why the name or entity was deprecated:
[[deprecated("Replaced by bar, which has an improved interface")]]
void foo(int);
The message must be a string literal.
For further details, see “Marking as deprecated in C++14”.
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How many String objects will be created when using a plus sign?
...n mind that there may be further optimizations at runtime. I'm just going by what IL is produced.
Finally, as regards interning, constants and literals are interned, but the value which is interned is the resulting constant value in the IL, not the literal. This means that you might get even fewe...
Automatically add all files in a folder to a target using CMake?
...regenerate." This is no longer recommeneded in CMAKE3.7 docs linked about by Hand1Cloud
– triple
Sep 13 '17 at 21:36
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Should I use a data.frame or a matrix?
...fficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer to its columns by name (via the compact $ operator)...
HTML if image is not found
... answered Nov 3 '11 at 13:01
Robby ShawRobby Shaw
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How do I clone a single branch in Git?
...n cloning the submodules.
See commit 132f600, commit 4731957 (21 Feb 2020) by Emily Shaffer (nasamuffin).
(Merged by Junio C Hamano -- gitster -- in commit b22db26, 05 Mar 2020)
clone: pass --single-branch during --recurse-submodules
Signed-off-by: Emily Shaffer
Acked-by: Jeff King
Previously, perf...