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Check if an array is empty or exists
... Array
Javascript has a dynamic type system. This means we can't guarantee what type of object a variable holds. There is a chance that we're not talking to an instance of Array.
supposedToBeArray = new SomeObject();
typeof supposedToBeArray.length; // => "undefined"
array = new Array();...
Check if a given key already exists in a dictionary and increment it
...import defaultdict
my_dict = defaultdict(int)
my_dict[key] += 1
will do what you want.
For regular Python dicts, if there is no value for a given key, you will not get None when accessing the dict -- a KeyError will be raised. So if you want to use a regular dict, instead of your code you would ...
How can I tell when HttpClient has timed out?
...) {} Only the general exception is caught, not the TaskCanceledException. What is wrong in my version of code?
– Naomi
Nov 22 '16 at 14:06
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How to use Session attributes in Spring-mvc
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What about RequestContextHolder?
– user1589188
May 29 '19 at 4:24
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Difference between application/x-javascript and text/javascript content types
What is the difference between these headers?
4 Answers
4
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How does having a dynamic variable affect performance?
... of dynamic in C#. I've read dynamic makes the compiler run again, but what does it do?
2 Answers
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How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
...well done for being the only one (of 5 I can see) who actually pointed out what was wrong with the code presented. +1
– Mike Woodhouse
Nov 26 '09 at 11:12
54
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Static variable inside of a function in C
What will be printed out? 6 6 or 6 7? And why?
13 Answers
13
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How do I create a multiline Python string with inline variables?
...; s.format(**d)
'This is an example with variables'
The closest thing to what you asked (in terms of syntax) are template strings. For example:
>>> from string import Template
>>> t = Template("This is an $example with $vars")
>>> t.substitute({ 'example': "example", 'v...
Ajax, back button and DOM updates
...wser history, so when the user clicks the back button, the hash changes to what it was before. So then it is implied that you will need some Javascript to monitor the has identifier and react when it is changed by the browser. Andreas Blixt has a hash monitoring script available.
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