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Check if key exists and iterate the JSON array using Python
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If all you want is to check if key exists or not
h = {'a': 1}
'b' in h # returns False
If you want to check if there is a value for key
h.get('b') # returns None
Return a default value if actual value is missing
h.get('b'...
Check whether variable is number or string in JavaScript
...ject.prototype.toString;
_.isString = function (obj) {
return toString.call(obj) == '[object String]';
}
This returns a boolean true for the following:
_.isString("Jonathan"); // true
_.isString(new String("Jonathan")); // true
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linq where list contains any in list
Using linq, how can I retrieve a list of items where its list of attributes match another list?
5 Answers
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How do I automatically update a timestamp in PostgreSQL
I want the code to be able to automatically update the time stamp when a new row is inserted as I can do in MySQL using CURRENT_TIMESTAMP.
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The role of #ifdef and #ifndef
In this what is the role of #ifdef and #ifndef , and what's the output?
4 Answers
4...
align right in a table cell with CSS
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Use
text-align: right
The text-align CSS property describes
how inline content like text is
aligned in its parent block element.
text-align does not control the
alignment of block elements itself,
only their i...
How to do error logging in CodeIgniter (PHP)
... wouldn't be publicly accessible- but you'll never know. Make sure to have all of this precautions in place if you change the default application/logs directory.
– Vincent Edward Gedaria Binua
Jan 29 '15 at 2:56
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What is a lambda expression in C++11?
... }
} f;
std::for_each(v.begin(), v.end(), f);
}
however this is not allowed, f cannot be passed to a template function in C++03.
The new solution
C++11 introduces lambdas allow you to write an inline, anonymous functor to replace the struct f. For small simple examples this can be cleaner t...
How do I download a tarball from GitHub using cURL?
I am trying to download a tarball from GitHub using cURL , but it does not seem to be redirecting:
5 Answers
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How to delete a file or folder?
...mdir() removes an empty directory.
shutil.rmtree() deletes a directory and all its contents.
Path objects from the Python 3.4+ pathlib module also expose these instance methods:
pathlib.Path.unlink() removes a file or symbolic link.
pathlib.Path.rmdir() removes an empty directory.
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