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How can I use map and receive an index as well in Scala?
... as follows:
import TraversableUtil._
List('a','b','c').map(doIndexed((i, char) => char + i))
which results in the list
List(97, 99, 101)
This way, you can use the usual Traversable-functions at the expense of wrapping your effective function. The overhead is the creation of the memoizing o...
jQuery $(“#radioButton”).change(…) not firing during de-selection
...Andomar's solution worked but this makes more sense to me. Using the class selector prevents having to change the function if the form changes or has a dynamic number of fields. Yay for necro votes! (though now 2 years later jQuery recommends using prop() instead of attr(). api.jquery.com/prop)
...
How do I check OS with a preprocessor directive?
...eturn a name of platform, if determined, otherwise - an empty string
const char *get_platform_name() {
return (PLATFORM_NAME == NULL) ? "" : PLATFORM_NAME;
}
int main(int argc, char *argv[]) {
puts(get_platform_name());
return 0;
}
Tested with GCC and clang on:
Debian 8
Windows (Min...
What is the difference between sigaction and signal?
...s defined in the C standard. Nevertheless, it has a number of undesirable characteristics that sigaction() avoids - unless you use the flags explicitly added to sigaction() to allow it to faithfully simulate the old signal() behaviour.
The signal() function does not (necessarily) block other signa...
Setting the selected value on a Django forms.ChoiceField
...t hand, but this Q/A comes up for searches related to trying to assign the selected value to a ChoiceField.
If you have already called super().__init__ in your Form class, you should update the form.initial dictionary, not the field.initial property. If you study form.initial (e.g. print self.init...
Identify if a string is a number
...$")
If you just want to know if it has one or more numbers mixed in with characters, leave off the ^ + and $.
Regex.IsMatch(input, @"\d")
Edit:
Actually I think it is better than TryParse because a very long string could potentially overflow TryParse.
...
How to find a hash key containing a matching value
...
You could use Enumerable#select:
clients.select{|key, hash| hash["client_id"] == "2180" }
#=> [["orange", {"client_id"=>"2180"}]]
Note that the result will be an array of all the matching values, where each is an array of the key and value.
...
What is the best way to paginate results in SQL Server
... sake of this example, let's assume that the query you're dealing with is
SELECT * FROM Orders WHERE OrderDate >= '1980-01-01' ORDER BY OrderDate
In this case, you would determine the total number of results using:
SELECT COUNT(*) FROM Orders WHERE OrderDate >= '1980-01-01'
...which may ...
How to create relationships in MySQL
...s defined as the default storage engine,can check using command (mysql> SELECT @@default_storage_engine;)
– Arun
Feb 18 at 4:00
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Accessing inactive union member and undefined behavior?
...object representation of an object of type T is the sequence of N unsigned char objects taken up by
the object of type T, where N equals sizeof(T). The value representation of an object is the set of bits that
hold the value of type T. For trivially copyable types, the value representation is a ...