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Why is Python 3.x's super() magic?
In Python 3.x, super() can be called without arguments:
1 Answer
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Using @property versus getters and setters
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Prefer properties. It's what they're there for.
The reason is that all attributes are public in Python. Starting names with an underscore or two is just a warning that the given attribute is an implementation detail that may not stay the same in future versions of the code. It doesn't preven...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former 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...
Using generic std::function objects with member functions in one class
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A non-static member function must be called with an object. That is, it always implicitly passes "this" pointer as its argument.
Because your std::function signature specifies that your function doesn't take any arguments (<void(void)>), you must bind the ...
Access nested dictionary items via a list of keys?
...ist, value):
getFromDict(dataDict, mapList[:-1])[mapList[-1]] = value
All but the last element in mapList is needed to find the 'parent' dictionary to add the value to, then use the last element to set the value to the right key.
Demo:
>>> getFromDict(dataDict, ["a", "r"])
1
>>&g...
Concatenating two lists - difference between '+=' and extend()
I've seen there are actually two (maybe more) ways to concatenate lists in Python:
One way is to use the extend() method:
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Convert PDF to clean SVG? [closed]
...t they often lose the font data, but don't seem to approximate a good, installed font. How does PDF display it if SVG can't?
– DanRedux
Apr 23 '12 at 21:30
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Is it possible to declare two variables of different types in a for loop?
...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above will give you:
int i set to 1
double f set to 1.0
std::string s set to "...
Output to the same line overwriting previous output?
...o need to import the sys module for this sort of simple usage. print() actually has a number of keyword arguments which can be used to greatly simplify code.
To use the same code on Python 2.6+, put the following line at the top of the file:
from __future__ import print_function
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Importing modules from parent folder
...t can matter if somewhere else then the parentdir, but in one of the paths allready specified in sys.path, there is another module with the name 'mymodule'. Inserting the parentdir as the first element of the sys.path list assures that the module from parentdir will be imported instead.
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