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What's the difference between => , ()=>, and Unit=>
... value (I'm simulating the setTimeout function in JavaScript, if you must know.)
4 Answers
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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...ll is just the default value, which we’ve been mutating all this time so now contains our new values. Since << doesn’t assign to the hash (there can never be assignment in Ruby without an = present†), we’ve never put anything into our actual hash. Instead we have to use <<= (whic...
Difference between a theta join, equijoin and natural join
... that the resultset has six columns and only contains one column for SNO.
Now consider a theta eqijoin, where the column names for the join must be explicitly specified (plus range variables S and SP are required):
SELECT * FROM S JOIN SP ON S.SNO = SP.SNO;
The resultset will have seven columns,...
Database design for audit logging
...
I don't know of any reference, but I'm sure someone has written something.
However, if the purpose is simply to have a record of what happened—the most typical use of an audit log—then why not simply keep everything:
timestamp
u...
How do I get the current GPS location programmatically in Android?
...n while you move, but if you want just one time, you need to call "getLastKnownLocation()"
– swiftBoy
May 6 '14 at 4:35
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Migrating from JSF 1.2 to JSF 2.0
...ith a rather large app written in JSF 1.2 .
JSF 1.2 is around 6 years old now. I need to upgrade to JSF 2.0. How painful will this be? I noticed that some attributes in custom tags have been changed etc.
...
What are the rules about using an underscore in a C++ identifier?
...itional type names.
While using these names for your own purposes right now might not cause a problem, they do raise the possibility of conflict with future versions of that standard.
Personally I just don't start identifiers with underscores. New addition to my rule: Don't use double undersco...
Differences between git remote update and fetch?
...Original answer with more details
xenoterracide's answer is 3.5 years old now, and Git has gone through several versions since then (it has gone from v1.6.5.5 to v1.8.3.2 as of this writing), and looking at the current documentation for git remote update and git fetch, it looks like they both can p...
In Matlab, when is it optimal to use bsxfun?
...viously, this functionality was available via the bsxfun function.
It is now recommended that you replace most uses of bsxfun with direct
calls to the functions and operators that support implicit expansion.
Compared to using bsxfun, implicit expansion offers faster speed,
better memory usag...
Ruby: extend self
...ways helps to think of extend as include inside the singleton class (also known as meta or eigen class).
You probably know that methods defined inside the singleton class are basically class methods:
module A
class << self
def x
puts 'x'
end
end
end
A.x #=> 'x'
Now th...