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is vs typeof
... +1: In the past I wondered why the C# compiler didn't compile typeof(string).TypeHandle to the ldtoken CIL instruction, but it looks like the CLR takes care of it in the JIT. It still takes a few extra opcodes but it's a more generalized application of the optimization.
–...
Bitwise operation and usage
...hexadecimal colours.
For example, here's a Python function that accepts a String like #FF09BE and returns a tuple of its Red, Green and Blue values.
def hexToRgb(value):
# Convert string to hexadecimal number (base 16)
num = (int(value.lstrip("#"), 16))
# Shift 16 bits to the right, a...
Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'
...that in "modern" languages like Java, C#, and Python, all objects have a toString/ToString/__str__ function that is called by the I/O routines. AFAIK, only C++ does it the other way around by using stringstream as the standard way of converting to a string.
Poor support for i18n
Iostream-based ou...
Insert Update trigger how to determine if insert or update
...aTable] FOR INSERT, UPDATE, DELETE
AS
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with caller queries SELECT statements.
-- If an update/insert/delete occurs on the main table, the number of records affected
-- should only be based on that table and not what records th...
A numeric string as array key in PHP
Is it possible to use a numeric string like "123" as a key in a PHP array, without it being converted to an integer?
11 A...
What does .class mean in Java?
....
object.getClass() returns the class of the given object.
For example:
String string = "hello";
System.out.println(string.getClass().toString());
This will output:
class java.lang.String
This is the class of the string object :)
...
Best way to create unique token in Rails?
...s Railscast on beta invitations. This produces a 40 character alphanumeric string.
Digest::SHA1.hexdigest([Time.now, rand].join)
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Do the JSON keys have to be surrounded by quotes?
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You are correct to use strings as the key. Here is an excerpt from RFC 4627 - The application/json Media Type for JavaScript Object Notation (JSON)
2.2. Objects
An object structure is represented as a pair of curly brackets
surrounding...
Why doesn't Java support unsigned ints?
...er performance rather than assuming it to be true. It is possible that the extra jiggery-pokery required to manipulate shorts rather than ints (which is usually the type that the processor 'likes to use') could actually be detrimental to performance in a particular application. Not always, but you s...
Why is “while ( !feof (file) )” always wrong?
... stream is still in the good() state.
C++, iostreams getline:
for (std::string line; std::getline(std::cin, line); ) {
consume(line);
}
The result we must use is again std::cin, just as before.
POSIX, write(2) to flush a buffer:
char const * p = buf;
ssize_t n = bufsize;
for (ss...