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Can Python print a function definition?
...pile a regular expression pattern, returning a pattern object."
return _compile(pattern, flags)
This will work in the interactive prompt, but apparently only on objects that are imported (not objects defined within the interactive prompt). And of course it will only work if Python can find th...
C++ equivalent of java's instanceof
...
Try using:
if(NewType* v = dynamic_cast<NewType*>(old)) {
// old was safely casted to NewType
v->doSomething();
}
This requires your compiler to have rtti support enabled.
EDIT:
I've had some good comments on this answer!
Every time you nee...
SASS - use variables across multiple files
...his:
I have a folder named utilities and inside that I have a file named _variables.scss
in that file i declare variables like so:
$black: #000;
$white: #fff;
then I have the style.scss file in which i import all of my other scss files like this:
// Utilities
@import "utilities/variables";
/...
How can I include a YAML file inside another?
...nstructor.
import yaml
import os
class Loader(yaml.SafeLoader):
def __init__(self, stream):
self._root = os.path.split(stream.name)[0]
super(Loader, self).__init__(stream)
def include(self, node):
filename = os.path.join(self._root, self.construct_scalar(node))...
Can PostgreSQL index array columns?
...0}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because we have only 2 records for this test...
SET enable_seqscan TO off;
EXPLAIN ANALYZE
SELECT * FROM "Test" WHERE "Column1" @> ARRAY[2...
Rename Files and Directories (Add Prefix)
...ll work for filenames with spaces in them:
for f in * ; do mv -- "$f" "PRE_$f" ; done
("--" is needed to succeed with files that begin with dashes, whose names would otherwise be interpreted as switches for the mv command)
...
Sending multipart/formdata with jQuery.ajax
...how is it possible to send this Data to the server? The resulting array ( $_POST ) on the serverside php-script is 0 ( NULL ) when using the file-input.
...
How can I access “static” class variables within class methods in Python?
...
Why not just Foo.bar, instead of self.__class__.bar?
– mk12
Sep 13 '09 at 20:59
15
...
How can I rename a field for all documents in MongoDB?
...ormer way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach(remap);
In MongoDB 3.2 you can also use
db.students.updateMany( {}, { $rename: { "oldname": "newname" } } )
...
Use cases for the 'setdefault' dict method
...ders -- some are optional, but you want defaults for them:
headers = parse_headers( msg ) # parse the message, get a dict
# now add all the optional headers
for headername, defaultvalue in optional_headers:
headers.setdefault( headername, defaultvalue )
...