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In Python how should I test if a variable is None, True or False
...
Don't fear the Exception! Having your program just log and continue is as easy as:
try:
result = simulate(open("myfile"))
except SimulationException as sim_exc:
print "error parsing stream", sim_exc
else:
if result:
print "result pass"
else:
print...
How to verify an XPath expression in Chrome Developers tool or Firefox's Firebug?
...here for more details):
Search in Elements panel like below
Execute $x() and $$() in Console panel, as shown in Lawrence's answer
Third party extensions (not really necessary in most of the cases, could be an overkill)
Here is how you search XPath in Elements panel:
Press F12 to open Chrome De...
How does “do something OR DIE()” work in PHP?
I'm writing a php app to access a MySQL database, and on a tutorial, it says something of the form
4 Answers
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SQL: IF clause within WHERE clause
...ion in most cases. In my case, I wanted the change the comparison operator and hence I used the next approach.
– Birla
Nov 15 '14 at 11:59
...
What is better, adjacency lists or adjacency matrices for graph problems in C++?
...ts or adjacency matrix, for graph problems in C++?
What are the advantages and disadvantages of each?
11 Answers
...
What is the meaning of prepended double colon “::”?
...wered Nov 24 '10 at 16:27
Wyatt AndersonWyatt Anderson
8,42811 gold badge1919 silver badges2424 bronze badges
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Return multiple values in JavaScript?
... first: getFirstValue(),
second: getSecondValue(),
};
}
And to access them:
var values = getValues();
var first = values.first;
var second = values.second;
Or with ES6 syntax:
const {first, second} = getValues();
* See this table for browser compatibility. Basically, all mod...
Cookies vs. sessions
...r the sake of creating a login system for my website, I read about cookies and sessions and their differences (cookies are stored in the user's browser and sessions on the server). At that time, I preferred cookies (and who does not like cookies?!) and just said: "who cares? I don't have any good de...
Ignoring time zones altogether in Rails and PostgreSQL
I'm dealing with dates and times in Rails and Postgres and running into this issue:
2 Answers
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What is the JSF resource library for and how should it be used?
The JSF <h:outputStylesheet> , <h:outputScript> and <h:graphicImage> components have a library attribute. What is this and how should this be used? There are a lot of examples on the web which use it as follows with the common content/file type css , js and img (or ima...