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Array include any value from another array?
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answered Oct 15 '10 at 11:55
NakilonNakilon
31.1k1212 gold badges9494 silver badges125125 bronze badges
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John Carmack's Unusual Fast Inverse Square Root (Quake III)
...s derived is something of a mystery.
To quote Gary Tarolli:
Which actually is doing a floating
point computation in integer - it took
a long time to figure out how and why
this works, and I can't remember the
details anymore.
A slightly better constant, developed by an expert mathemat...
In CMake, how can I test if the compiler is Clang?
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Top-Master
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answered Nov 17 '16 at 11:26
AntonioAntonio
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How do you write a migration to rename an ActiveRecord model and its table in Rails?
...ble_name
end
end
I had to go and rename the model declaration file manually.
Edit:
In Rails 3.1 & 4, ActiveRecord::Migration::CommandRecorder knows how to reverse rename_table migrations, so you can do this:
class RenameOldTableToNewTable < ActiveRecord::Migration
def change
rena...
Why does `a == b or c or d` always evaluate to True?
...r is more literal minded.
if name == "Kevin" or "Jon" or "Inbar":
is logically equivalent to:
if (name == "Kevin") or ("Jon") or ("Inbar"):
Which, for user Bob, is equivalent to:
if (False) or ("Jon") or ("Inbar"):
The or operator chooses the first argument with a positive truth value:
if ("Jon")...
How to convert a number to string and vice versa in C++
...o-number conversion and vice-versa are built in into the standard library. All the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const string& str, size_t *idx = 0);
double stod(const string& str, size_t *id...
What is `params.require(:person).permit(:name, :age)` doing in Rails 4?
All the examples of strong parameters in Rails 4 docs use
2 Answers
2
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Creating PHP class instance with a string
...able functions & methods.
$func = 'my_function';
$func('param1'); // calls my_function('param1');
$method = 'doStuff';
$object = new MyClass();
$object->$method(); // calls the MyClass->doStuff() method.
share
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Disable Browser Link - which toolbar
...olbar, but that toolbar doesn't show up in my visual studio. I've enabled all the debug toolbars but still no browser link button.
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What's the point of map in Haskell, when there is fmap?
...make an answer to draw attention to augustss's comment:
That's not actually how it happens. What happened was that the type of map was generalized to cover Functor in Haskell 1.3. I.e., in Haskell 1.3 fmap was called map. This change was then reverted in Haskell 1.4 and fmap was introduced. The ...