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Best way to test for a variable's existence in PHP; isset() is clearly broken
...any normal array. Consequently, see 1.
Functionality that existed only to predict how these functions are about to behave (e.g. "will there be a key 'foo' in the array returned by get_defined_vars?") is superfluous, since you can simply run the function and find out with no ill effects.
4a. Variab...
Floating point vs integer calculations on modern hardware
...algorithm play a significant role here, so that no general comparison will predict the performance gap on your problem.
For example, integer addition is commutative, so if the compiler sees a loop like you used for a benchmark (assuming the random data was prepared in advance so it wouldn't obscure...
How to generate a random number in C++?
... of application you should first decide if you really need truly random (unpredictable) data. Notable case when you do most certainly need true randomness is information security - e.g. generating symmetric keys, asymmetric private keys, salt values, security tokens, etc.
However security-grade rand...
Is floating point math broken?
...rval Arithmetic combined with variations of the IEEE 754 rounding modes to predict rounding errors, and correct them. Because of its low relative error compared to other rounding modes, round to nearest even digit (in the last place), is the default rounding mode of IEEE-754.
Note that the default ...
When and why are database joins expensive?
...erferes with other join strategies. But if you have buckets of disk space, predictable patterns of access, and a tendency to process much or all of it, then precomputing a join can be very worthwhile.
You can also figure out the access paths your operation typically uses and precompute all the joi...
What is the best Distributed Brute Force countermeasure?
...uldn't be too difficult to pick the correct one, since people tend to pick predictable types of images (even images from their own Flickr albums!)
– Jens Roland
Jan 27 '09 at 2:51
...
Split string into an array in Bash
...<"$string"; declare -p a;
## declare -a a=([0]="Paris" [1]=" France")
Predictably, the unaccounted surrounding whitespace got pulled into the field values, and hence this would have to be corrected subsequently through trimming operations (this could also be done directly in the while-loop). Bu...
What is a monad?
...ning for IO operations also ensures that they are executed in a linear and predictable order, just like statements in an imperative language.
This brings us to the first program most people will write in Haskell:
main :: IO ()
main = do
putStrLn ”Hello World”
The do keyword is superflu...
The definitive guide to form-based website authentication [closed]
...ts against network sniffing attacks. The value of the cookie should not be predictable. Where a cookie referencing a non-existent session is presented, its value should be replaced immediately to prevent session fixation.
PART II: How To Remain Logged In - The Infamous "Remember Me" Checkbox
Persist...
How does PHP 'foreach' actually work?
...ird edge-case issues, while PHP 7's more involved approach results in more predictable and consistent behavior.
As a last preliminary, it should be noted that PHP uses reference counting and copy-on-write to manage memory. This means that if you "copy" a value, you actually just reuse the old value...