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Reference: Comparing PHP's print and echo
...ssion:
5 + echo 6; // syntax error
In contrast, print expr, can alone form a statement:
print 5; // valid
Or, be part of an expression:
$x = (5 + print 5); // 5
var_dump( $x ); // 6
One might be tempted to think of print as if it were a unary operator, like ! or ~ however it i...
How to pass objects to functions in C++?
...hat was used in the calling context, and cannot be null. All operations performed inside the function apply to the object outside the function. This convention is not available in Java or C.
Pass by value (and pass-by-pointer)
The compiler will generate a copy of the object in the calling context ...
What would cause an algorithm to have O(log log n) complexity?
...ar way of shrinking down the size of a problem that yields runtimes of the form O(log log n). Instead of dividing the input in half at each layer, what happens if we take the square root of the size at each layer?
For example, let's take the number 65,536. How many times do we have to divide this ...
Is multiplication and division using shift operators in C actually faster?
... These comments make it sound like you're giving up on potential performance from telling the compiler how to do its job. This is not the case. You actually get better code from gcc -O3 on x86 with return i*10 than from the shift version. As someone who looks at compiler output a lot (see m...
What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … }
...d give it a name that makes sense in the local scope.
There is a slight performance advantage since it is faster to look things up in the local scope instead of having to walk up the scope chain into the global scope.
There are benefits for compression (minification).
Earlier I described how these...
Why do I need 'b' to encode a string with Base64?
...
>>> data = b'test'
>>> for byte in data:
... print(format(byte, '08b'), end=" ")
...
01110100 01100101 01110011 01110100
>>>
If you interpret that binary data as a single integer, then this is how you would convert it to base-10 and base-64 (table for base-64):
ba...
Read/write to Windows registry using Java
...ion("hkey=" + hkey);
}
}
/**
* Read value(s) and value name(s) form given key
* @param hkey HKEY_CURRENT_USER/HKEY_LOCAL_MACHINE
* @param key
* @return the value name(s) plus the value(s)
* @throws IllegalArgumentException
* @throws IllegalAccessException
* @throws In...
Generic method multiple (OR) type constraint
...ossiblities:
Define more than one method that defines each possible transformation, behavior, or whatever. That's Botz's answer. In the programming world this is referred to as Overloading the method.
Define a base class or interface that knows how to do all the things that you need for the meth...
Which iomanip manipulators are 'sticky'?
...at setw appears to behave differently is because there are requirements on formatted output operations to explicitly .width(0) the output stream.
The following is the discussion that lead to the above conclusion:
Looking at the code the following manipulators return an object rather than a stre...
Break a previous commit into multiple commits
...n check out the content of that commit over my working directory using the form of git checkout which takes both a commit and a file location. Here I use . as the file location to replace the whole working copy:
git checkout 65dfb6a .
Don't miss the dot on the end!
This will check out, and stage...