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When would anyone use a union? Is it a remnant from the C-only days?
...pace to work with, or when you're developing an API (or something similar) and you want to force the end user to have only one instance of several objects/types at one time. Are these two guesses even close to right?
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Evaluating a mathematical expression in a string
...ppend(toks[0])
def pushUMinus(self, strg, loc, toks):
if toks and toks[0] == '-':
self.exprStack.append('unary -')
def __init__(self):
"""
expop :: '^'
multop :: '*' | '/'
addop :: '+' | '-'
integer :: ['+' | '-'] '0'..'9'+
...
PHP Sort Array By SubArray Value
...
Well he just gave you the function to use. And you're going to have to accept that there's not always a built-in function to do what you want, you have to write it yourself. Comparison functions just require a return of 1, 0, or -1 indicating the sort order for two el...
How can I suppress all output from a command using Bash?
...
The following sends standard output to the null device (bit bucket).
scriptname >/dev/null
And if you also want error messages to be sent there, use one of (the first may not work in all shells):
scriptname &>/dev/null
scriptname >...
Can you use a trailing comma in a JSON object?
...ed to worry about all browsers.
In general I try turn the problem around, and add the comma before the actual value, so you end up with code that looks like this:
s.append("[");
for (i = 0; i < 5; ++i) {
if (i) s.append(","); // add the comma only if this isn't the first entry
s.appendF("\"...
One SVN repository or many?
...ce.
Management of multiple vs. single mainly comes down to access control and maintenance.
Access control for a single repository can be contained in a single file; Multiple repositories are may require multiple files. Maintenance has similar issues - one big backup, or a lot of little backups.
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Using comparison operators in Scala's pattern matching system
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You can add a guard, i.e. an if and a boolean expression after the pattern:
a match {
case 10 => println("ten")
case x if x > 10 => println("greater than ten")
case _ => println("less than ten")
}
Edit: Note that this is more than...
Deploying my application at the root in Tomcat
...couple of options:
Remove the out-of-the-box ROOT/ directory from tomcat and rename your war file to ROOT.war before deploying it.
Deploy your war as (from your example) war_name.war and configure the context root in conf/server.xml to use your war file :
<Context path="" docBase="war_name" de...
Bash if statement with multiple conditions throws an error
I'm trying to write a script that will check two error flags, and in case one flag (or both) are changed it'll echo-- error happened. My script:
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Hash and salt passwords in C#
...- which the membership provider does to put them into config files. Hashes and salts are binary blobs, you don't need to convert them to strings unless you want to put them into text files.
In my book, Beginning ASP.NET Security, (oh finally, an excuse to pimp the book) I do the following
static ...