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Is the practice of returning a C++ reference variable evil?
...
In general, returning a reference is perfectly normal and happens all the time.
If you mean:
int& getInt() {
int i;
return i; // DON'T DO THIS.
}
That is all sorts of evil. The stack-allocated i will go away and you are referring to nothing. This is also evil:
int& get...
Duplicating a MySQL table, indices, and data
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This should have been the accepted answer. As this copies all the indexes including primary key and auto_increment
– Channaveer Hakari
Oct 11 '18 at 6:06
add ...
How to read a large file line by line?
...e line from the file.
echo $file->fgets();
}
// Unset the file to call __destruct(), closing the file handle.
$file = null;
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Get the Query Executed in Laravel 3/4
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Laravel 4+
In Laravel 4 and later, you have to call DB::getQueryLog() to get all ran queries.
$queries = DB::getQueryLog();
$last_query = end($queries);
Or you can download a profiler package. I'd recommend barryvdh/laravel-debugbar, which is pretty neat. You can read f...
What are conventions for filenames in Go?
...he go test tool.
Files with os and architecture specific suffixes automatically follow those same constraints, e.g. name_linux.go will only build on linux, name_amd64.go will only build on amd64. This is the same as having a //+build amd64 line at the top of the file
See the docs for the go build...
How do I select a random value from an enumeration?
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Use Enum.GetValues to retrieve an array of all values. Then select a random array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (in...
Iterating over each line of ls -l output
... instead of parsing output of "ls -l" line by line, you could iterate over all files and do an "ls -l" for each individual file like this:
for x in * ; do echo `ls -ld $x` ; done
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Why is semicolon allowed in this python snippet?
...ot warrant the use of semicolons to end statements.
So why is this (below) allowed?
15 Answers
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How to initialize private static members in C++?
...t be done outside of any function.
Note: Matt Curtis: points out that C++ allows the simplification of the above if the static member variable is of const int type (e.g. int, bool, char). You can then declare and initialize the member variable directly inside the class declaration in the header fil...
Why use apparently meaningless do-while and if-else statements in macros?
...into
if (corge)
f(corge); g(corge);
else
gralt();
which is syntactically incorrect, as the else is no longer associated with the if. It doesn't help to wrap things in curly braces within the macro, because a semicolon after the braces is syntactically incorrect.
if (corge)
{f(corge); g(co...