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Linq to Entities join vs groupjoin
...ement);
yield return resultSelector(outerElement, lookup[key]);
}
Read more here:
Reimplementing LINQ to Objects: Part 19 - Join
Reimplementing LINQ to Objects: Part 22 - GroupJoin
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What's the difference between lists and tuples?
... there is the namedtuple in Python, which makes sense because a tuple is already supposed to have structure. This underlines the idea that tuples are a light-weight alternative to classes and instances.
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How to show math equations in general github's markdown(not github's blog)
...e embed code. Svg renders well on resize. HTML allows LaTeX to be easily read when you are looking at the source. Copy the embed code from the bottom of the page and paste it into your markdown.
<img src="https://latex.codecogs.com/svg.latex?\Large&space;x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}...
How to overcome root domain CNAME restrictions?
...ates domain names without subdomain in front of them are not valid. If you read the RFC carefully, however, you'll find that this is not exactly what it says. In fact, RFC 1912 states:
Don't go overboard with CNAMEs. Use them when renaming hosts, but plan to get rid of them (and inform your user...
Python: print a generator expression?
...st comprehension out of it! However, this will obviously not work if you already have a generator object. Doing that will just make a list of one generator:
>>> foo = (x*x for x in range(10))
>>> [foo]
[<generator object <genexpr> at 0xb7559504>]
In that case you wil...
Show Youtube video source into HTML5 video tag?
...e a JSFiddle as a live example: http://jsfiddle.net/zub16fgt/
And you can read more about the YouTube API here: https://developers.google.com/youtube/iframe_api_reference#Getting_Started
The Code can also be found below
In your HTML:
<div id="player"></div>
In your Javascript:...
Set a persistent environment variable from cmd.exe
...et an env var "foo" with value of "bar":
setx foo bar
Though it's worth reading the 'notes' that are displayed if you print the usage (setx /?), in particular:
2) On a local system, variables created or modified by this tool will be available in future command windows but not in the current C...
How do I programmatically shut down an instance of ExpressJS for testing?
... There will be a handful of different startup options for the server (like reading config options from a file, loading state from a datastore, etc) that it would be nice to test in the same framework I test everything else. I'd also like to have tests that, for instance, shutdown the server, bring i...
What's a correct and good way to implement __hash__()?
...no practical use in this context because the builtin Python string types already provide a __hash__ method; we don't need to roll our own. The question is how to implement __hash__ for a typical user-defined class (with a bunch of properties pointing to built-in types or perhaps to other such user-d...
Pointer to class data member “::*”
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@eee I recommend you to read about reference parameters. What I did is basically equivalent to what you did.
– Johannes Schaub - litb
Aug 25 '11 at 18:55
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