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Using -performSelector: vs. just calling the method
...iblings performSelectorInBackground:withObject: and performSelectorOnMainThread:withObject:waitUntilDone: are often more useful. For spawning a background thread, and for calling back results to the main thread from said background thread.
– PeyloW
Sep 30 '09 a...
Do you have to put Task.Run in a method to make it async?
...synchronous" (async) means that it may yield control back to the calling thread before it starts. In an async method, those "yield" points are await expressions.
This is very different than the term "asynchronous", as (mis)used by the MSDN documentation for years to mean "executes on a background t...
Why '&&' and not '&'?
...lopers typically worry about stuff like this - and you never know who will read the answers; so it's always best to document even the borderline/extreme cases.
– Jonathan Dickinson
Sep 7 '11 at 12:30
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Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
... being "as fast as C" is more about generic C than highly optimized multithreaded cache-aware C libraries used for numerics. For numerics, Python is just used to ferry around pointers to big arrays. So PyPy being "as fast as C" means "your pointers+metadata get moved around as fast as C". Not a big ...
What does “program to interfaces, not implementations” mean?
One stumbles upon this phrase when reading about design patterns.
7 Answers
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Is it safe to ignore the possibility of SHA collisions in practice?
... @Hristo I think yes, one would take that risk. A nuclear power plant already has a far higher chance of exploding due to other things, like mechanical failure, human error in building it or operator error while running it, and we are already taking those chances. If SHA-256 collisions were the o...
Why should C++ programmers minimize use of 'new'?
...u don't know how much memory you need at compile time. For instance, when reading a text file into a string, you usually don't know what size the file has, so you can't decide how much memory to allocate until you run the program.
You want to allocate memory which will persist after leaving the cu...
What are the differences between git remote prune, git prune, git fetch --prune, etc
...anches you've created but never pushed to the server would be deleted, so tread carefully: git branch -r | awk '{print $1}' | egrep -v -f /dev/fd/0 <(git branch -vv | grep origin) | awk '{print $1}'
– Jason Walton
Sep 11 '14 at 2:59
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Design patterns or best practices for shell scripts [closed]
...PTION_MSG), the first containing the exception type and the second a human readable message.
When you call a function, the parameters of the function are assigned to the special vars $0, $1 etc. I suggest you to put them into more meaningful names. declare the variables inside the function as local...
Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
...ile or other information would be better than what they currently provide (read: better than nothing).
Your best option is to run it in the debugger with debugging information, and your IDE will break at the offending line (rather clearly demonstrating that useful information is in fact available)...