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Python: Checking if a 'Dictionary' is empty doesn't seem to work
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A dictionary can be automatically cast to boolean which evaluates to False for empty dictionary and True for non-empty dictionary.
if myDictionary: non_empty_clause()
else: empty_clause()
If this looks too idiomatic, you can also test len(myDictionary) fo...
How to get the unix timestamp in C#
...you are expected to call it on an instance of DateTimeOffset. You can also cast any instance of DateTime, though beware the timezone.
To get the current timestamp:
DateTimeOffset.UtcNow.ToUnixTimeSeconds()
To get the timestamp from a DateTime:
DateTime foo = DateTime.UtcNow;
long unixTime = ((D...
Performing user authentication in Java EE / JSF using j_security_check
...regarding user authentication for a web application making use of JSF 2.0 (and if any components do exist) and Java EE 6 core mechanisms (login/check permissions/logouts) with user information hold in a JPA entity. The Oracle Java EE tutorial is a bit sparse on this (only handles servlets).
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How do I dynamically assign properties to an object in TypeScript?
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What's the point of TypeScript if I have to cast so many things to any in order to use it? Just becomes extra noise in my code.. :/
– AjaxLeung
Jul 22 '16 at 19:04
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New Array from Index Range Swift
...laring your array to begin with.
EDIT:
To fix your function, you have to cast your Slice to an array:
func aFunction(numbers: Array<Int>, position: Int) -> Array<Int> {
var newNumbers = Array(numbers[0..<position])
return newNumbers
}
// test
aFunction([1, 2, 3], 2) // ...
PostgreSQL: Difference between text and varchar (character varying)
What's the difference between the text data type and the character varying ( varchar ) data types?
9 Answers
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Can I convert long to int?
...o when implementing a CompareTo operation, for instance, you can't happily cast the result of subtracting one long from another to an int and return that; for some values, your comparison would yield an incorrect result.
– T.J. Crowder
Apr 10 '11 at 8:56
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Restful way for deleting a bunch of items
...riation might be, to do away with the javascript confirm on the same page, and instead, create the selection and redirect to it, showing a confirm message on that page. In other words:
From:
http://example.com/resources/
do a
POST with a selection of the ID's to:
http://example.com/resources/sele...
SQL query to select dates between two dates
...instead of implicit conversion of datestring constants. - and Date between CAST('2011/02/25'AS DATETIME) and CAST('2011/02/27'AS DATETIME)
– tponthieux
Feb 26 '11 at 9:27
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Max or Default?
...unctions. To summarize what I found, you can get around this limitation by casting to a nullable within your select. My VB is a little rusty, but I think it'd go something like this:
Dim x = (From y In context.MyTable _
Where y.MyField = value _
Select CType(y.MyCounter, Integer?)...