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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
p...
Convert objective-c typedef to its string equivalent
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This is really a C question, not specific to Objective-C (which is a superset of the C language). Enums in C are represented as integers. So you need to write a function that returns a string given an enum value. There are many ways to...
Why does “_” (underscore) match “-” (hyphen)?
...you are in a pattern context. e.g. inside a LIKE statement. When replacing all _ with an - : UPDATE sys_file set identifier = REPLACE(identifier, '_', '-') WHERE identifier LIKE '%\_%';. Notice the escaping inside LIKE and no escaping inside REPLACE. (I find it strange though that you are not in a p...
When to use in vs ref vs out
...ss you need ref.
It makes a big difference when the data needs to be marshalled e.g. to another process, which can be costly. So you want to avoid marshalling the initial value when the method doesn't make use of it.
Beyond that, it also shows the reader of the declaration or the call whether the ...
How to replace spaces in file names using a bash script
...whole question is about micro-optimizing more or less. Isn't it fun, after all? ;-)
– Michael Krelin - hacker
Apr 26 '10 at 18:33
17
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Why are preprocessor macros evil and what are the alternatives?
I have always asked this but I have never received a really good answer; I think that almost any programmer before even writing the first "Hello World" had encountered a phrase like "macro should never be used", "macro are evil" and so on, my question is: why? With the new C++11 is there a real alte...
ORA-12514 TNS:listener does not currently know of service requested in connect descriptor
We have an application running locally where we're experiencing the following error:
25 Answers
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$(document).ready equivalent without jQuery
...ent
if ( document.addEventListener ) {
// Use the handy event callback
document.addEventListener( "DOMContentLoaded", function(){
document.removeEventListener( "DOMContentLoaded", arguments.callee, false );
jQuery.ready();
}, false );
// If IE...
Dynamically updating plot in matplotlib
...out the more modern animation examples in the matplotlib documentation. Finally, the animation API defines a function FuncAnimation which animates a function in time. This function could just be the function you use to acquire your data.
Each method basically sets the data property of the object be...
Perl flags -pe, -pi, -p, -w, -d, -i, -t?
...eem to be mostly made up of punctuation :-)
The command line switches are all detailed in perlrun. (available from the command line by calling perldoc perlrun)
Going into the options briefly, one-by-one:
-p: Places a printing loop around your command so that it acts on each
line of standard ...