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What is 'Pattern Matching' in functional languages?

...wesome. Algebraic data types in a nutshell ML-like functional languages allow you define simple data types called "disjoint unions" or "algebraic data types". These data structures are simple containers, and can be recursively defined. For example: type 'a list = | Nil | Cons of 'a * 'a ...
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What does numpy.random.seed(0) do?

... I'm not very familiar with NumPy's random state generator stuff, so I'd really appreciate a layman's terms explanation of this. ...
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Using “super” in C++

... the first time C++ was standardized. Dag Bruck proposed this extension, calling the base class "inherited." The proposal mentioned the multiple inheritance issue, and would have flagged ambiguous uses. Even Stroustrup was convinced. After discussion, Dag Bruck (yes, the same person making the p...
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django - why is the request.POST object immutable?

... It's a bit of a mystery, isn't it? Several superficially plausible theories turn out to be wrong on investigation: So that the POST object doesn't have to implement mutation methods? No: the POST object belongs to the django.http.QueryDict class, which implements a full set ...
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Deserialize JSON into C# dynamic object?

...ere. I modified the code slightly to fix a bug and suit my coding style. All you need is this code and a reference to System.Web.Extensions from your project: using System; using System.Collections; using System.Collections.Generic; using System.Collections.ObjectModel; using System.Dynamic; usin...
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Easy way to dismiss keyboard?

...ere's an easier way to dismiss the keyboard without having to loop through all my controls and resigning them all as the first responder. I guess the question is.. How would I get the current first responder to the keyboard? ...
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No connection could be made because the target machine actively refused it?

... If this happens always, it literally means that the machine exists but that it has no services listening on the specified port, or there is a firewall stopping you. If it happens occasionally - you used the word "sometimes" - and retrying succeeds, it is l...
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Django queries - id vs pk

...ry key field i.e. you don't need to care whether the primary key field is called id or object_id or whatever. It also provides more consistency if you have models with different primary key fields. share | ...
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Are unused CSS images downloaded?

... "unused" and thusly, any images won't be downloaded. Chrome 26 (possibly all of them, not sure), does download CSS images if they are applied to the <noscript> element, even when JS is enabled. (It isn't immediately clear to me why though, perhaps this is a bug?). It does not download CSS i...
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Remove a marker from a GoogleMap

...tead of the MarkerOptions object that you used to create it). This object allows you to change the marker state later on. When you are finished with the marker, you can call Marker.remove() to remove it from the map. As an aside, if you only want to hide it temporarily, you can toggle the visibil...