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Is pass-by-value a reasonable default in C++11?
...ar(foo f); // want to obtain a copy of f
bar(const foo& f); // want to read f
bar(foo& f); // want to modify f
All other signatures should be used only sparingly, and with good justification. The compiler will now pretty much always work these out in the most efficient way. You can just ge...
The written versions of the logical operators
...an it is helpful. I'm sure if it were normal, they would be much easier to read, but people are so used to && and || anything else just gets distracting.
EDIT: I have seen a very slight increase in their usage since I posted this, however. I still avoid them.
...
Callback functions in C++
...
A function pointer is the 'simplest' (in terms of generality; in terms of readability arguably the worst) type a callback can have.
Let's have a simple function foo:
int foo (int x) { return 2+x; }
1.1 Writing a function pointer / type notation
A function pointer type has the notation
return...
Jelly Bean DatePickerDialog — is there a way to cancel?
--- Note to moderators: Today (July 15), I've noticed that someone already faced this problem here . But I'm not sure if it's appropriate to close this as a duplicate, since i think I provided a much better explanation of the issue. I'm not sure if I should edit the other question and paste this ...
How to overcome TypeError: unhashable type: 'list'
...you're done
with open('filename.txt', 'rb') as f:
d = {}
# Here we use readlines() to split the file into a list where each element is a line
for line in f.readlines():
# Now we split the file on `x`, since the part before the x will be
# the key and the part after the value
line =...
What is “stdafx.h” used for in Visual Studio?
...instead of starting from scratch, the compiler starts compiling from the already saved results of compiling everything in stdafx.h.
I don't believe that this trick is unique to Microsoft compilers, nor do I think it was an original development.
For Microsoft compilers, the setting that controls th...
How are zlib, gzip and zip related? What do they have in common and how are they different?
... and are in varying, small amounts of use. The only method in truly widespread use in the ZIP format is method 8, Deflate, and to some smaller extent method 0, which is no compression at all. Virtually every .zip file that you will come across in the wild will use exclusively methods 8 and 0, like...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...e results, e.g. same results on any compiler. Floating point numbers are already not exact. It is seldomly inappropriate to compile with -fassociative-math.
– Paul Draper
Aug 24 '14 at 16:11
...
Erlang's 99.9999999% (nine nines) reliability
...ong says here:
The AXD301 has achieved a NINE nines reliability (yes, you read that right, 99.9999999%). Let’s put this in context: 5 nines is reckoned to be good (5.2 minutes of downtime/year). 7 nines almost unachievable ... but we did 9.
Why is this? No shared state, plus a sophisticated error...
Ruby custom error classes: inheritance of the message attribute
...
raise already sets the message so you don't have to pass it to the constructor:
class MyCustomError < StandardError
attr_reader :object
def initialize(object)
@object = object
end
end
begin
raise MyCustomError.new("...