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Assign a variable inside a Block to a variable outside a Block
... *aPerson = nil;
For more details, please refer to this tutorial: Blocks and Variables
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Generating Guids in Ruby
I have problem that is really easily solved with Guids.
10 Answers
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How to create streams from string in Node.Js?
...g"])
readable.on("data", (chunk) => {
console.log(chunk) // will be called once with `"input string"`
})
Note that at least between 10.17 and 12.3, a string is itself a iterable, so Readable.from("input string") will work, but emit one event per character. Readable.from(["input string"]) wil...
std::string formatting like sprintf
...mixed cout and printfs are output correctly. Disabling this link (with a call to cout.sync_with_stdio(false)) causes c++'s streams to outperform stdio, at least as of MSVC10.
– Jimbo
Jan 20 '13 at 21:15
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How to extract the n-th elements from a list of tuples?
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@Wayne Werner: Yep. This stuff was all just passive knowledge (I don't often use it) - but it's good to be reminded now and then so you know where / what to look for...
– Daren Thomas
Jul 22 '10 at 13:14
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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What's wrong with nullable columns in composite primary keys?
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Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonally, NULL is al...
Converting datetime.date to UTC timestamp in Python
...le (e.g., via tzlocal.get_localzone()) to get access to the tz database on all platforms. Also, utcfromtimestamp() may fail and mktime() may return non-POSIX timestamp if "right" timezone is used.
To convert datetime.date object that represents date in UTC without calendar.timegm():
DAY = 24*60*...
Impossible to Install PG gem on my mac with Mavericks
I'm trying to install the pg gem in order to work again with my rails projects. But I get this error:
26 Answers
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Django Admin - Disable the 'Add' action for a specific model
...also register MyAdmin like: admin.site.register(MyModel, MyModelAdmin) Add all into the admin.py of the models`s app folder.
– djangonaut
Apr 23 '18 at 9:16
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