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Where does the “flatmap that s***” idiomatic expression in Scala come from?
What is so powerful about flatmap that it deserves such a place in the Scala folklore?
4 Answers
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What's the longest possible worldwide phone number I should consider in SQL varchar(length) for phon
...ly storing 20 characters in each, err on the side of caution and just make it 50.
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Why do we need C Unions?
... and floats:
union
{
int i;
float f;
} u;
// Convert floating-point bits to integer:
u.f = 3.14159f;
printf("As integer: %08x\n", u.i);
Although this is technically undefined behavior according to the C standard (you're only supposed to read the field which was most recently written), it wil...
How do I calculate the date in JavaScript three months prior to today?
... that one month ago means the same day of the month on the previous month citation needed. But more than half the time, that is 31 days ago, not 30. And if today is the 31st of the month (and it isn't August or Decemeber), that day of the month doesn't exist in the previous month.
Interestingly, ...
Open Cygwin at a specific folder
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When you install Cygwin (or if you’ve already installed it, download it again and start setup again to run an update), make sure that you select the chere package under the "Shells" category.
After Cygwin is launched, open up a Cygwin terminal (as an administrator) and type the c...
Is there a good JavaScript minifier? [closed]
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edited Sep 23 '17 at 16:54
Dave Jarvis
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Are HTTP headers case-sensitive?
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Header names are not case sensitive.
From RFC 2616 - "Hypertext Transfer Protocol -- HTTP/1.1", Section 4.2, "Message Headers":
Each header field consists of a name followed by a colon (":") and the field value. Field names are case-insensitive.
Th...
Check if a given key already exists in a dictionary
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and if you wanted to always ensure a default value for any key you can either use dict.setdefault() repeatedly or defaultdict from the collections module, like so:
from collections import defaultdict
d = defaultdict(int)
for i in range(100):
d[i % 10] += 1
but in general, the in keyword ...
Does MySQL ignore null values on unique constraints?
I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way?
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Static link of shared library function in gcc
....apps/2004-05/0436.html
You need the static version of the library to link it.
A shared library is actually an executable in a special format
with entry points specified (and some sticky addressing issues
included). It does not have all the information needed to
link statically.
You can't statically...