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Why covariance and contravariance do not support value type
IEnumerable<T> is co-variant but it does not support value type, just only reference type. The below simple code is compiled successfully:
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Should I be using object literals or constructor functions?
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If you don't have behaviour associated with an object (i.e. if the object is just a container for data/state), I would use an object literal.
var data = {
foo: 42,
bar: 43
};
Apply the KISS principle. If you don't need an...
How to trigger a file download when clicking an HTML button or JavaScript
This is crazy but I don't know how to do this, and because of how common the words are, it's hard to find what I need on search engines. I'm thinking this should be an easy one to answer.
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Can an int be null in Java?
...e check(root) method can return null then you can safely cast it to int by doing something like this: int data = (Integer)check(node);
– sactiw
Oct 11 '12 at 14:06
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Differences in string compare methods in C#
...omparing string in C# is pretty simple. In fact there are several ways to do it. I have listed some in the block below. What I am curious about are the differences between them and when one should be used over the others? Should one be avoided at all costs? Are there more I haven't listed?
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Regular expression to match numbers with or without commas and decimals in text
...common task, but all the answers I see here so far will accept inputs that don't match your number format, such as ,111, 9,9,9, or even .,,.. That's simple enough to fix, even if the numbers are embedded in other text. IMHO anything that fails to pull 1,234.56 and 1234—and only those numbers—out...
Elasticsearch query to return all records
...uals a number you believe is bigger than your dataset)
BUT, elasticsearch documentation suggests for large result sets, using the scan search type.
EG:
curl -XGET 'localhost:9200/foo/_search?search_type=scan&scroll=10m&size=50' -d '
{
"query" : {
"match_all" : {}
}
}'
an...
MySQL Error 1153 - Got a packet bigger than 'max_allowed_packet' bytes
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You probably have to change it for both the client (you are running to do the import) AND the daemon mysqld that is running and accepting the import.
For the client, you can specify it on the command line:
mysql --max_allowed_packet=100M -u root -p database < dump.sql
Also, change the my....
How to find time complexity of an algorithm
...e simplify 2N + 2 machine instructions to describe this as just O(N).
Why do we remove the two 2s ?
We are interested in the performance of the algorithm as N becomes large.
Consider the two terms 2N and 2.
What is the relative influence of these two terms as N becomes large? Suppose N is a mil...
How to convert an object to a byte array in C#
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@Smith: Yes, you can do that, just write them after each other. The BinaryWriter will write them in a format that the BinaryReader can read, as long as you write and read them in the same order.
– Guffa
May ...