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Should I pass a shared_ptr by reference? [duplicate]
...general, you should pass the shared pointer as a straight copy. This gives it its intended semantics: Every scope that contains a copy of the shared pointer keeps the object alive by virtue of its "share" in the ownership.
The only reason not to always pass by value is that copying a shared pointer...
Why does C++11's lambda require “mutable” keyword for capture-by-value, by default?
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It requires mutable because by default, a function object should produce the same result every time it's called. This is the difference between an object orientated function and a function using a global variable, effectively...
Setting the correct encoding when piping stdout in Python
...thon program, the Python interpreter gets confused about encoding and sets it to None. This means a program like this:
10 A...
How to place and center text in an SVG rectangle
...y solution to center text horizontally and vertically in SVG:
Set the position of the text to the absolute center of the element in which you want to center it:
If it's the parent, you could just do x="50%" y ="50%".
If it's another element, x would be the x of that element + half its width (and...
Why does ++[[]][+[]]+[+[]] return the string “10”?
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If we split it up, the mess is equal to:
++[[]][+[]]
+
[+[]]
In JavaScript, it is true that +[] === 0. + converts something into a number, and in this case it will come down to +"" or 0 (see specification details below).
Therefore...
Generating PDF files with JavaScript
... into PDF files from a web page and I was hoping I could do this entirely within JavaScript. I need to be able to draw text, images and simple shapes. I would love to be able to do this entirely in the browser.
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Using global variables in a function
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You can use a global variable within other functions by declaring it as global within each function that assigns a value to it:
globvar = 0
def set_globvar_to_one():
global globvar # Needed to modify global copy of globvar
globvar = 1
def prin...
Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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Java Singleton and Synchronization
Please clarify my queries regarding Singleton and Multithreading:
8 Answers
8
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Retrieve the position (X,Y) of an HTML element relative to the browser window
I want to know how to get the X and Y position of HTML elements such as img and div in JavaScript relative to the browser window.
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