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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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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...
How can I see the raw SQL queries Django is running?
...t the output of the query is not valid SQL, because:
"Django never actually interpolates the parameters: it sends the query and the parameters separately to the database adapter, which performs the appropriate operations."
From Django bug report #17741.
Because of that, you should not send qu...
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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How do I select a random value from an enumeration?
...
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...
addEventListener vs onclick
...se);
Using this approach (DOM Level 2 events), you can attach a theoretically unlimited number of events to any single element. The only practical limitation is client-side memory and other performance concerns, which are different for each browser.
The examples above represent using an anonymous...
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...
Gradients in Internet Explorer 9
...soft.com/testdrive/Graphics/CSSGradientBackgroundMaker/Default.html
Note: all of these browsers also support rgb/rgba in place of hexadecimal notation.
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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...
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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