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Whether a variable is undefined [duplicate]
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jQuery.val() and .text() will never return 'undefined' for an empty selection. It always returns an empty string (i.e. ""). .html() will return null if the element doesn't exist though.You need to do:
if(page_name != '')
For other va...
git-svn not a git command?
...oblem. Whenever I run git svn , I get an error saying it isn't a git command, yet there is documentation for it that I can pull up using git help . Is there something wrong with my install, or am I just missing something here?
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Sorting Python list based on the length of the string
... such that cmp(x, y) returns -1 if x is less than y, 0 if x is equal to y, and 1 if x is greater than y.
Of course, you can instead use the key parameter:
xs.sort(key=lambda s: len(s))
This tells the sort method to order based on whatever the key function returns.
EDIT: Thanks to balpha and Ruslan ...
Why can't overriding methods throw exceptions broader than the overridden method?
I was going through SCJP 6 book by Kathe sierra and came across this explanations of throwing exceptions in overridden method. I quite didn't get it. Can any one explain it to me ?
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Use JSTL forEach loop's varStatus as an ID
... edited May 2 '19 at 8:56
Andrew Tobilko
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answered Jul 6 '11 at 17:50
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Set Value of Input Using Javascript Function
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And yet he gave the correct answer. There are newbies that will find this question based on this answer.
– Matthew Nichols
May 9 '16 at 12:38
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What's the best way of scraping data from a website? [closed]
...web scraping framework. Later on you may decide that they are too limiting and you can put together your own stack of libraries but without a lot of scraping experience your design will be much worse than pjscrape or scrapy.
Note: I use the terms crawling and scraping basically interchangeable here...
C# elegant way to check if a property's property is null
In C#, say that you want to pull a value off of PropertyC in this example and ObjectA, PropertyA and PropertyB can all be null.
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Using helpers in model: how do I include helper dependencies?
I'm writing a model that handles user input from a text area. Following the advice from http://blog.caboo.se/articles/2008/8/25/sanitize-your-users-html-input , I'm cleaning up the input in the model before saving to database, using the before_validate callback.
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Print content of JavaScript object? [duplicate]
...re a cross-browser way of doing something similar?
– Anderson Green
Oct 2 '12 at 1:30
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In recen...