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How can I troubleshoot my Perl CGI script?
...ral framework for working through
problems with Perl CGI scripts and originally appeared on Perlmonks as Troubleshooting Perl CGI Scripts. It is not a complete guide to every
problem that you may encounter, nor a tutorial on bug squashing. It
is just the culmination of my experience debugging CGI ...
What exactly does Perl's “bless” do?
...to a hash (most common case), to an array (not so common), to a scalar (usually this indicates an inside-out object), to a regular expression, subroutine or TYPEGLOB (see the book Object Oriented Perl: A Comprehensive Guide to Concepts and Programming Techniques by Damian Conway for useful examples)...
How do I prevent Eclipse from hanging on startup?
I am using Eclipse 3.3 ("Europa"). Periodically, Eclipse takes an inordinately long time (perhaps forever) to start up. The only thing I can see in the Eclipse log is:
...
Why do we need extern “C”{ #include } in C++?
...
C and C++ are superficially similar, but each compiles into a very different set of code. When you include a header file with a C++ compiler, the compiler is expecting C++ code. If, however, it is a C header, then the compiler expects the data cont...
Replace a value if null or undefined in JavaScript
... boolean value but the first value that can be converted to true.
Additionally use an array of objects instead of one single object:
var options = {
filters: [
{
name: 'firstName',
value: 'abc'
}
]
};
var filter = options.filters[0] || ''; // is {n...
Truncate a string straight JavaScript
...
Use the substring method:
var length = 3;
var myString = "ABCDEFG";
var myTruncatedString = myString.substring(0,length);
// The value of myTruncatedString is "ABC"
So in your case:
var length = 3; // set to the number of characters you want to keep
var pathname = document.referrer;
...
Flags to enable thorough and verbose g++ warnings
.... I then removed from that list the set of warnings that I feel do not actually indicate something bad is happening, or else have too many false positives to be used in a real build. I commented as to why each of the ones I excluded were excluded. This is my final set of suggested warnings:
-pedant...
Python != operation vs “is not”
...right hand side and the left hand side are the very same object. No methodcalls are done, objects can't influence the is operation.
You use is (and is not) for singletons, like None, where you don't care about objects that might want to pretend to be None or where you want to protect against object...
Short description of the scoping rules?
...
Actually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These rules are specific to variable names, not attributes. If you reference it without a period, these rules apply.)
LEGB Rule
Local — N...
How do I log a Python error with debug information?
...g.exception("message")
Output:
ERROR:root:message
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
ZeroDivisionError: integer division or modulo by zero
@Paulo Cheque notes, "be aware that in Python 3 you must call the logging.exception method just inside the ex...