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Why does the use of 'new' cause memory leaks?
...of type T with automatic storage duration. It will get cleaned up automatically when it goes out of scope.
When you write new T() you're creating an object of type T with dynamic storage duration. It won't get cleaned up automatically.
You need to pass a pointer to it to delete in order to clean...
Throwing cats out of windows
Imagine you're in a tall building with a cat. The cat can survive a fall out of a low story window, but will die if thrown from a high floor. How can you figure out the longest drop that the cat can survive, using the least number of attempts?
...
What's the difference between a proc and a lambda in Ruby?
...ept the resulting Proc objects check the number of parameters passed when called.
An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb):1>
p.call 1, 2 # => 5
p.call 1 # => NoMethodError: undefined method `**' for nil:NilClass
p.call 1, 2, 3 # => 5
l = lamb...
Parsing command-line arguments in C?
...
Really thorough answer, thanks Christian (upvoted). However, mac users should be aware that the argp approach isn't cross-platform compatible. As I found here, Argp is a non-standardized glibc API extension. It is available i...
Storing JSON in database vs. having a new column for each key
...opularity, I figured it was worth an update.
When this question was originally posted, MySQL had no support for JSON data types and the support in PostgreSQL was in its infancy. Since 5.7, MySQL now supports a JSON data type (in a binary storage format), and PostgreSQL JSONB has matured significant...
Can anyone explain IEnumerable and IEnumerator to me? [closed]
...n you write code like:
foreach (Foo bar in baz)
{
...
}
it's functionally equivalent to writing:
IEnumerator bat = baz.GetEnumerator();
while (bat.MoveNext())
{
bar = (Foo)bat.Current
...
}
By "functionally equivalent," I mean that's actually what the compiler turns the code into. Yo...
How can I access the MySQL command line with XAMPP for Windows?
...
On the Mac, or at least on my Mac using a default install, I accessed it at:
/Applications/xampp/xamppfiles/bin/mysql -uroot -p
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SHA512 vs. Blowfish and Bcrypt [closed]
...ome on-board RAM.
Note: bcrypt is an algorithm that uses Blowfish internally. It is not an encryption algorithm itself. It is used to irreversibly obscure passwords, just as hash functions are used to do a "one-way hash".
Cryptographic hash algorithms are designed to be impossible to reverse. In...
When should I use cross apply over inner join?
...r
),
t AS
(
SELECT 1 AS id
UNION ALL
SELECT 2
)
SELECT *
FROM t
JOIN q
ON q.rn <= t.id
runs for almost 30 seconds, while this one:
WITH t AS
(
SELECT 1 AS id
UNION ALL
SELECT 2
...
When should I really use noexcept?
...n it's obvious that the function will never throw.
When can I realistically expect to observe a performance improvement after using noexcept? [...] Personally, I care about noexcept because of the increased freedom provided to the compiler to safely apply certain kinds of optimizations.
It se...