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How to find the type of an object in Go?
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Based on a barebones benchmark, the reflect approach is surprisingly more efficient gist.github.com/mrap/7f08c9549289b6aea2923c27888e7e3e
– Mike Rapadas
Apr 6 '17 at 20:53
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What are the mechanics of short string optimization in libc++?
...ng
Note: __compressed_pair is essentially a pair optimized for the Empty Base Optimization, aka template <T1, T2> struct __compressed_pair: T1, T2 {};; for all intents and purposes you can consider it a regular pair. Its importance just comes up because std::allocator is stateless and thus e...
How do I convert between big-endian and little-endian values in C++?
...32 bit numbers:
unsigned long _byteswap_ulong(unsigned long value);
For 64 bit numbers:
unsigned __int64 _byteswap_uint64(unsigned __int64 value);
8 bit numbers (chars) don't need to be converted.
Also these are only defined for unsigned values they work for signed integers as well.
For floa...
sqlite database default time value 'now'
Is it possible in a sqlite database to craete a table that has a timestamp column that default to DATETIME('now') ?
7 Ans...
Google Authenticator implementation in Python
...ected with incorrect value of secret key (it must be correct parameter for base64.b32decode() function).
Below I post full working solution with explanation on how to use it.
Code
The following code is enough. I have also uploaded it to GitHub as separate module called onetimepass (available here...
Container View Controller Examples [closed]
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Ditto. It's not my favorite demo code example, but it does properly implement VC containers as well as memory management -- it's really important that your child view controllers get released when they are no longer visible.
– memm...
What does the brk() system call do?
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If you want to do fancy memory allocation, either base it oon top of malloc, or on top of mmap. Don't touch brk and sbrk, they are relics from the past that do more harm than good (even the manpages tell you to stay clear of them!)
– Eloff
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Regex: match everything but specific pattern
...ttern (e.g. any - empty, too - string not starting with foo):
Lookahead-based solution for NFAs:
^(?!foo).*$
^(?!foo)
Negated character class based solution for regex engines not supporting lookarounds:
^(([^f].{2}|.[^o].|.{2}[^o]).*|.{0,2})$
^([^f].{2}|.[^o].|.{2}[^o])|^.{0,2}$
a string ...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
...ady be fetched and in cache, the branch target maybe or maybe not. With a 64 bit CPU you grab at least 64 bits at a time. Depending on DRAM interleave, it may be 2x 3x or more bits that get grabbed.
– Bryce
Feb 15 '17 at 19:39
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How to have Android Service communicate with Activity
... I have a Service that will run in the background and do some gps and time based logging. I will have an Activity that will be used to start and stop the Service.
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