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Boost Statechart vs. Meta State Machine
...tly boost contains two separate libraries for state machines: Statechart and Meta State Machine (MSM). The taglines give very similar descriptions:
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How to overcome “datetime.datetime not JSON serializable”?
...h requires no dependencies.
As you are using mongoengine (per comments) and pymongo is a dependency, pymongo has built-in utilities to help with json serialization:
http://api.mongodb.org/python/1.10.1/api/bson/json_util.html
Example usage (serialization):
from bson import json_util
import json...
What is the difference between a shim and a polyfill?
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A shim is any piece of code that performs interception of an API call and provides a layer of abstraction. It isn't necessarily restricted to a web application or HTML5/CSS3.
A polyfill is a type of shim that retrofits legacy browsers with modern HTML5/CSS3 features usually using Javascript or ...
Naming convention for Scala constants?
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The officially recommended style (and I do mean officially) is the first style, camel case with first letter are upper case. It's laid down clearly by Odersky on Programming in Scala.
The style is also followed by the standard library, and has some support i...
When is it better to use String.Format vs string concatenation?
...the performance hit, but to be honest it'll be minimal if present at all - and this concatenation version doesn't need to parse the format string.
Format strings are great for purposes of localisation etc, but in a case like this concatenation is simpler and works just as well.
With C# 6
String i...
make_unique and perfect forwarding
Why is there no std::make_unique function template in the standard C++11 library? I find
6 Answers
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What is eager loading?
...on't do any calculations until you access an element of the result matrix; and
Over-eager loading: this is where you try and anticipate what the user will ask for and preload it.
I hope that makes sense in the context you're seeing it.
Let me give you a "Webby" example.
Imagine a page with rollo...
Assign pandas dataframe column dtypes
...you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x ...
How to detect internet speed in JavaScript?
...an I create a JavaScript page that will detect the user’s internet speed and show it on the page? Something like “your internet speed is ??/?? Kb/s” .
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What is the easiest way to parse an INI file in Java?
...format of this ini files is the common windows style, with header sections and key=value pairs, using # as the character for commenting.
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