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What are the differences between Rust's `String` and `str`?
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String is the dynamic heap string type, like Vec: use it when you need to own or modify your string data.
str is an immutable1 sequence of UTF-8 bytes of dynamic length somewhere in memory. Since the size is unknown, one can only handle it behind a pointer. This means that str most commonly2 app...
Can't launch my app in Instruments: At least one target failed to launch
...for your target and under "Profile [App Name]" set the Build Configuration to Debug (it's usually Release by default).
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PyPy — How can it possibly beat CPython?
...gement (which is what CPython does with its counting) can be slower than automatic management in some cases.
Limitations in the implementation of the CPython interpreter preclude certain optimisations that PyPy can do (eg. fine grained locks).
As Marcelo mentioned, the JIT. Being able to on the f...
How to perform Unwind segue programmatically?
Using storyboard this is very easy. You just drag the action to "Exit". But how should I call it from my code?
10 Answers
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Which is faster: while(1) or while(2)?
.../resources per iteration.
Using gcc, I compiled the two following programs to assembly at varying levels of optimization:
int main(void) {
while(1) {}
return 0;
}
int main(void) {
while(2) {}
return 0;
}
Even with no optimizations (-O0), the generated assembly was identical for bo...
Generate Java classes from .XSD files…?
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JAXB does EXACTLY what you want. It's built into the JRE/JDK starting at 1.6
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How to parse a date? [duplicate]
I am trying to parse this date with SimpleDateFormat and it is not working:
5 Answers
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What are forward declarations in C++?
At: http://www.learncpp.com/cpp-tutorial/19-header-files/
8 Answers
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iOS Safari – How to disable overscroll but allow scrollable divs to scroll normally?
I'm working on an iPad-based web app, and need to prevent overscrolling so that it seems less like a web page. I'm currently using this to freeze the viewport and disable overscroll:
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Read a file line by line assigning the value to a variable
... echo "Text read from file: $line"
done < "$1"
If the above is saved to a script with filename readfile, it can be run as follows:
chmod +x readfile
./readfile filename.txt
If the file isn’t a standard POSIX text file (= not terminated by a newline character), the loop can be modified to ...