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Xcode doesn't show the line that causes a crash
Every time my app crashes Xcode highlights the UIApicationMain() call in the main() function as the line that caused the crash. In some cases that used to be normal (segmentation fault for example) but the crash I am trying to deal with is a simple SIGABRT with detailed information logged in the con...
Is “IF” expensive?
... work.
The current instruction to be executed is stored in something typically called the instruction pointer (IP) or program counter (PC); these terms are synonymous, but different terms are used with different architectures. For most instructions, the PC of the next instruction is just the curre...
How do I capture SIGINT in Python?
...f KeyboardInterruptException is implemented as a SIGINT handler or if it really only catches Ctrl+C presses, but either way, using a signal handler makes your intent explicit (at least, if your intent is the same as OP's). More importantly though, with a signal you don't have to wrap try-catches ar...
Android: upgrading DB version and adding new table
...
1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...
Is it possible to forward-declare a function in Python?
...rwards is impossible, what about defining it in some other module?
Technically you still define it first, but it's clean.
You could create a recursion like the following:
def foo():
bar()
def bar():
foo()
Python's functions are anonymous just like values are anonymous, yet they can be ...
What exactly are unmanaged resources?
...
Managed resources basically means "managed memory" that is managed by the garbage collector. When you no longer have any references to a managed object (which uses managed memory), the garbage collector will (eventually) release that memory for you...
Can I embed a custom font in an iPhone application?
...plist, you can use your custom fonts as any other font in IB or programatically.
There is an ongoing thread on Apple Developer Forums:
https://devforums.apple.com/thread/37824 (login required)
And here's an excellent and simple 3 steps tutorial on how to achieve this (broken link removed)
Add y...
How does deriving work in Haskell?
Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasse s (like Show , Eq ) by deriving from them.
...
How do I expire a PHP session after 30 minutes?
...ms with filesystems where atime tracking is not available.
So it additionally might occur that a session data file is deleted while the session itself is still considered as valid because the session data was not updated recently.
And second:
session.cookie_lifetime
session.cookie_lifetime ...
Use of 'use utf8;' gives me 'Wide character in print'
...t three bytes make up your character, the last one is the line-feed.
The call to print sends these four characters to STDOUT. Your console then works out how to display these characters. If your console is set to use UTF8, then it will interpret those three bytes as your single character and that i...