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What is recursion and when should I use it?
...ation which can eliminate some classes of stack overflow. Put succinctly: if a function's return expression is simply the result of a function call, then you don't need to add a new level onto the stack, you can reuse the current one for the function being called. Regrettably, few imperative langu...
Disable building workspace process in Eclipse
... i disable it because it is taking a long time to complete and i dont know if it is necessary. Thank you
4 Answers
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How do I pass parameters into a PHP script through a webpage?
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$argument1 = $_GET['argument1'];
$argument2 = $_GET['argument2'];
?>
If you want the script to run regardless of where you call it from (command line or from the browser) you'll want something like the following:
EDIT: as pointed out by Cthulhu in the comments, the most direct way to test whi...
Escape regex special characters in a Python string
...ring)
Return string with all non-alphanumerics backslashed; this is useful if you want to match an arbitrary literal string that may have regular expression metacharacters in it.
As of Python 3.7 re.escape() was changed to escape only characters which are meaningful to regex operations.
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Convert a row of a data frame to vector
...tly more explicit way to get to the same result.
As @Josh comments below, if you have a not-completely-numeric (alphabetic, factor, mixed ...) data frame, you need as.character(df[1,]) instead.
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Storing custom objects in an NSMutableArray in NSUserDefaults
...dataRepresentingSavedArray = [currentDefaults objectForKey:@"savedArray"];
if (dataRepresentingSavedArray != nil)
{
NSArray *oldSavedArray = [NSKeyedUnarchiver unarchiveObjectWithData:dataRepresentingSavedArray];
if (oldSavedArray != nil)
objectArray = [[NSMutableArray alloc] initWit...
A semantics for Bash scripts?
... its own right, but with features designed to make it easy to interact specifically with the operating system and filesystem. The POSIX shell's (hereafter referred to just as "the shell") semantics are a bit of a mutt, combining some features of LISP (s-expressions have a lot in common with shell wo...
Objective-C Runtime: best way to check if class conforms to protocol?
I have a Class (but no instance) and need to know if it conforms to a certain protocol. However, Class can be subclassed several times and class_conformsToProtocol() ignores protocols declared on superclasses.
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Using CMake with GNU Make: How can I see the exact commands?
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The top google hit recommends "if you want to see solely the g++ command lines, you should use grep & Co. - if possible - in connection with verbose Makefiles". Perhaps developers with lots of cmake experience have other advice.
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Checking if a string is empty or null in Java [duplicate]
... to check for null or empty or string containing only spaces is like this:
if(str != null && !str.trim().isEmpty()) { /* do your stuffs here */ }
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