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Swift and mutating struct
...answers WHY, by default, the properties of a value type cannot be modified from within its instance methods. you make hints that its because structs default to immutable, but i dont think that is true
– Joseph Knight
Jun 5 '14 at 19:49
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Functional programming - is immutability expensive? [closed]
...nsider this reference implementation in Haskell (I don’t know Scala …) from the Haskell introduction:
qsort [] = []
qsort (x:xs) = qsort lesser ++ [x] ++ qsort greater
where lesser = (filter (< x) xs)
greater = (filter (>= x) xs)
The first disadvantage is the choice ...
How do I get a reference to the app delegate in Swift?
... explain what setRoot() does and when to call it. e.g. is it ok to call it from a ViewController? From a Unit test where window is not set yet? More context would be great.
– Houman
Dec 24 '19 at 16:52
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How do I byte-compile everything in my .emacs.d directory?
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You can use the --batch flag to recompile from the command line.
To recompile all, do
emacs --batch --eval '(byte-recompile-directory "~/.emacs.d")'
or to recompile a single file as from a Makefile,
emacs --batch --eval '(byte-compile-file "your-elisp-file.el")'...
How can I check the syntax of Python script without executing it?
.... Which is good practice anyway. I've even adopted this for shell scripts. From here it's a small step to unit testing.
– Henk Langeveld
Aug 10 '12 at 12:07
1
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Sound alarm when code finishes
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This one seems to work on both Windows and Linux* (from this question):
def beep():
print("\a")
beep()
In Windows, can put at the end:
import winsound
winsound.Beep(500, 1000)
where 500 is the frequency in Herz
1000 is the duration in miliseconds
To work on ...
Difference between Visibility.Collapsed and Visibility.Hidden
...ace the control would take is 'collapsed', hence the name.
The exact text from the MSDN:
Collapsed: Do not display the element, and do not reserve space for it in layout.
Hidden: Do not display the element, but reserve space for the element in layout.
Visible: Display the element.
S...
Git: how to reverse-merge a commit?
...git revert <commit>
It's also possible to actually remove a commit from an arbitrary point in the past by rebasing and then resetting, but you really don't want to do that if you have already pushed your commits to another repository (or someone else has pulled from you).
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How to read lines of a file in Ruby
I was trying to use the following code to read lines from a file. But when reading a file , the contents are all in one line:
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Clang vs GCC for my Linux Development project
...lt;(std::ostream& out, Student const& s) {
^
In file included from /tmp/webcompile/_25327_1.cc:1:
In file included from /usr/include/c++/4.3/string:49:
In file included from /usr/include/c++/4.3/bits/localefwd.h:47:
/usr/include/c++/4.3/iosfwd:134:33: note: previous definition is here
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