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add column to mysql table if it does not exist
...
Note that INFORMATION_SCHEMA isn't supported in MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good.
One solution used by frameworks that use database migrations is...
How do I access the request object or any other variable in a form's clean() method?
... no reason to do it this way.
A much better way is to override the form's __init__ method to take an extra keyword argument, request. This stores the request in the form, where it's required, and from where you can access it in your clean method.
class MyForm(forms.Form):
def __init__(self, *...
Greenlet Vs. Threads
... can i use gevent in this case to read faster import hashlib def checksum_md5(filename): md5 = hashlib.md5() with open(filename,'rb') as f: for chunk in iter(lambda: f.read(8192), b''): md5.update(chunk) return md5.digest()
– Soumya
...
Flattening a shallow list in Python [duplicate]
...ndexable sequence, consider itertools.chain and company.
>>> list_of_menuitems = [['image00', 'image01'], ['image10'], []]
>>> import itertools
>>> chain = itertools.chain(*list_of_menuitems)
>>> print(list(chain))
['image00', 'image01', 'image10']
It will work...
Add CSS or JavaScript files to layout head from views or partial views
...Format);
}
}
public class ItemRegistrar
{
private readonly string _format;
private readonly IList<string> _items;
public ItemRegistrar(string format)
{
_format = format;
_items = new List<string>();
}
public ItemRegistrar Add(string url)
...
How assignment works with Python list slice?
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Is a[:] = some_list equivalent to a = some_list[:] or a = some_list?
– jadkik94
May 17 '12 at 10:42
2
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How do I get the path to the current script with Node.js?
...r looking through the documentation again. What I was looking for were the __filename and __dirname module-level variables.
__filename is the file name of the current module. This is the resolved absolute path of the current module file. (ex:/home/kyle/some/dir/file.js)
__dirname is the directory ...
Is there any difference between “foo is None” and “foo == None”?
...pares the same object instance
Whereas == is ultimately determined by the __eq__() method
i.e.
>>> class Foo(object):
def __eq__(self, other):
return True
>>> f = Foo()
>>> f == None
True
>>> f is None
False
...
Recommended way of making React component/div draggable
...;
return result;
};
class Draggable extends React.PureComponent {
_relX = 0;
_relY = 0;
_ref = React.createRef();
_onMouseDown = (event) => {
if (event.button !== 0) {
return;
}
const {scrollLeft, scrollTop, clientLeft, clientTop} = docume...
Comparing mongoose _id and strings
...ls() method. With your example, results.userId.equals(AnotherMongoDocument._id). The ObjectID type also has a toString() method, if you wish to store a stringified version of the ObjectID in JSON format, or a cookie.
If you use ObjectID = require("mongodb").ObjectID (requires the mongodb-native lib...