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What are the key differences between Scala and Groovy? [closed]
...uff you can do in Java. Note, Scala's static type system is substantially more uniform and sophisticated than Java's.
Groovy is syntactically influenced by Java but semantically influenced more by languages like Ruby.
Scala is syntactically influenced by both Ruby and Java. It is semantically in...
Convert column classes in data.table
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What does a tilde do when it precedes an expression?
... If you profiled your application and found a bottleneck, it could be made more performant by using bitwise tricks (as one possible tool in a much bigger bag).
It's also a (generally) unclear trick to turn indexOf()'s found return value into truthy (while making not found as falsy) and people often...
How to select the first element with a specific attribute using XPath
...store/book[@location='US'][1] works only with simple structure.
Add a bit more structure and things break.
With
<bookstore>
<category>
<book location="US">A1</book>
<book location="FIN">A2</book>
</category>
<category>
<book location="FI...
What are “named tuples” in Python?
...((pt1[0]-pt2[0])**2 + (pt1[1]-pt2[1])**2)
Using a named tuple it becomes more readable:
from collections import namedtuple
Point = namedtuple('Point', 'x y')
pt1 = Point(1.0, 5.0)
pt2 = Point(2.5, 1.5)
from math import sqrt
line_length = sqrt((pt1.x-pt2.x)**2 + (pt1.y-pt2.y)**2)
However, named...
What is the difference between Lisp-1 and Lisp-2?
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Isn't a Lisp-2 more confusing having functions and variables with the same names then?
– appshare.co
Jan 2 '11 at 15:43
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How do I check if an object has a specific property in JavaScript?
... - 2.0.1 and older - but those versions of the browser are rarely used any more.)
If what you're looking for is if an object has a property on it that is iterable (when you iterate over the properties of the object, it will appear) then doing: prop in object will give you your desired effect.
Sinc...
What are the primary differences between Haskell and F#? [closed]
...ork.
Listen to the Software Engineering radio with Simon Peyton Jones for more info on Haskell: Episode 108: Simon Peyton Jones on Functional Programming and Haskell
share
ed...
Should I use tag for icons instead of ? [closed]
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What does it mean by select 1 from table?
...ally meaningful (that said, I will use it because others use it and it is "more obvious" immediately. Of course, that might be a viscous chicken vs. egg issue, but I don't generally dwell)).
SELECT * FROM TABLE1 T1 WHERE EXISTS (
SELECT 1 FROM TABLE2 T2 WHERE T1.ID= T2.ID
);
Basically, the...