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“Comparison method violates its general contract!”
...ce A > B and B > C, then it must be the case that A > C. However, if your comparator is invoked on A and C, it would return zero, meaning A == C. This violates the contract and hence throws the exception.
It's rather nice of the library to detect this and let you know, rather than behave e...
HTML5 LocalStorage: Checking if a key exists [duplicate]
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Quoting from the specification:
The getItem(key) method must return the current value associated with the given key. If the given key does not exist in the list associated with the object then this method must return null.
You should actual...
How to disable HTML links
...We, probably, need to define a CSS class for pointer-events: none but what if we reuse the disabled attribute instead of a CSS class? Strictly speaking disabled is not supported for <a> but browsers won't complain for unknown attributes. Using the disabled attribute IE will ignore pointer-eve...
Count work days between two dates
...ET @StartDate = '2008/10/01'
SET @EndDate = '2008/10/31'
SELECT
(DATEDIFF(dd, @StartDate, @EndDate) + 1)
-(DATEDIFF(wk, @StartDate, @EndDate) * 2)
-(CASE WHEN DATENAME(dw, @StartDate) = 'Sunday' THEN 1 ELSE 0 END)
-(CASE WHEN DATENAME(dw, @EndDate) = 'Saturday' THEN 1 ELSE 0 END)
If you...
How do I query if a database schema exists
... our build process we run a database update script as we deploy code to 4 different environments. Further, since the same query will get added to until we drop a release into production it has to be able to run multiple times on a given database. Like this:
...
How can I check if an element exists in the visible DOM?
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It seems some people are landing here, and simply want to know if an element exists (a little bit different to the original question).
That's as simple as using any of the browser's selecting method, and checking it for a truthy value (generally).
For example, if my element had an id o...
How to check if a query string value is present via JavaScript?
How can I check if the query string contains a q= in it using JavaScript or jQuery?
10 Answers
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How to check if a list is empty in Python? [duplicate]
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if not myList:
print "Nothing here"
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What is the pythonic way to detect the last element in a 'for' loop?
...ial case instead of the last one:
first = True
for data in data_list:
if first:
first = False
else:
between_items()
item()
This will work for any iterable, even for those that have no len():
file = open('/path/to/file')
for line in file:
process_line(line)
#...
(Built-in) way in JavaScript to check if a string is a valid number
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To check if a variable (including a string) is a number, check if it is not a number:
This works regardless of whether the variable content is a string or number.
isNaN(num) // returns true if the variable does NOT contain a...