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How can I check the size of a collection within a Django template?
I have a list in my Django template. I want to do something only if the size of the list is greater than zero.
7 Answers...
How to check if a variable is not null?
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They are not equivalent. The first will execute the block following the if statement if myVar is truthy (i.e. evaluates to true in a conditional), while the second will execute the block if myVar is any value other than null.
The only values that are not truthy in JavaScript are the following (a...
Using try vs if in python
Is there a rationale to decide which one of try or if constructs to use, when testing variable to have a value?
9 Ans...
How do I decode HTML entities in Swift?
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This answer was last revised for Swift 5.2 and iOS 13.4 SDK.
There's no straightforward way to do that, but you can use NSAttributedString magic to make this process as painless as possible (be warned that this method will strip all HTML tags as well).
Rem...
Iterating over each line of ls -l output
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Set IFS to newline, like this:
IFS='
'
for x in `ls -l $1`; do echo $x; done
Put a sub-shell around it if you don't want to set IFS permanently:
(IFS='
'
for x in `ls -l $1`; do echo $x; done)
Or use while | read instead:
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Passing base64 encoded strings in URL
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There are additional base64 specs. (See the table here for specifics ). But essentially you need 65 chars to encode: 26 lowercase + 26 uppercase + 10 digits = 62.
You need two more ['+', '/'] and a padding char '='. But none of them are url friendly, so just use different chars for th...
Example use of “continue” statement in Python?
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Here's a simple example:
for letter in 'Django':
if letter == 'D':
continue
print("Current Letter: " + letter)
Output will be:
Current Letter: j
Current Letter: a
Current Letter: n
Current Letter: g
Current Letter: o
It continues to the next iteration of the l...
What is the difference between range and xrange functions in Python 2.X?
...f besides the anecdotal so far that it is faster) or what besides that is different about
28 Answers
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Convert a Unicode string to a string in Python (containing extra symbols)
...oblem of not being able to save unicode to a file sounds like an entirely different issue worthy of a separate question
– Mark Roddy
Jul 30 '09 at 16:03
5
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nil detection in Go
... // not nil
or
var config *Config // nil
Then you'll be able to check if
if config == nil {
// then
}
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