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Where is the documentation for the values() method of Enum?
...places :
Enum Types, from The Java Tutorials
The compiler automatically adds some special methods when it creates
an enum. For example, they have a static values method that returns an
array containing all of the values of the enum in the order they are
declared. This method is commonl...
What is the point of Lookup?
... via that key in an efficient manner (rather than just iterating over them all, which is what GroupBy lets you do).
For example, you could take a load of .NET types and build a lookup by namespace... then get to all the types in a particular namespace very easily:
using System;
using System.Collec...
How can I declare and use Boolean variables in a shell script?
......
if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_flat=true
# ...do something interesting...
if $the_world_is_flat ; then
echo 'Be careful not to fall off!'
fi
From: Usi...
Find out if ListView is scrolled to the bottom?
...r_list_id:
// Make your calculation stuff here. You have all your
// needed info from the parameters of this function.
// Sample calculation to determine if the last
// item is fully visible.
final int lastItem = firstVisibleItem + ...
When to add what indexes in a table in Rails
...
Should I add "index" to all the foreign keys like "xxx_id"?
It would be better, because it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be created aut...
Is leaked memory freed up when the program exits?
...s a reference to, and thus can no longer free. The OS still keeps track of all the memory allocated to a process, and will free it when that process terminates.
In the vast majority of cases the OS will free the memory - as is the case with normal "flavors" of Windows, Linux, Solaris, etc. However ...
Is it safe to ignore the possibility of SHA collisions in practice?
...rgued that any unlucky event with a probability lower than that is not actually very important.
If we have a "perfect" hash function with output size n, and we have p messages to hash (individual message length is not important), then probability of collision is about p2/2n+1 (this is an approximat...
Error: could not find function … in R
...the name of your function correctly? Names are case sensitive.
Did you install the package that contains the function? install.packages("thePackage") (this only needs to be done once)
Did you attach that package to the workspace ?
require(thePackage) or library(thePackage) (this should be done ever...
Given a number, find the next higher number which has the exact same set of digits as the original n
...the right, you find the first pair-of-digits such that the left-digit is smaller than the right-digit. Let's refer to the left-digit by "digit-x". Find the smallest number larger than digit-x to the right of digit-x, and place it immediately left of digit-x. Finally, sort the remaining digits in ...
What is a “cache-friendly” code?
...her end of the memory spectrum (DRAM), the memory is very cheap (i.e. literally millions of times cheaper) but takes hundreds of cycles after a request to receive the data. To bridge this gap between super fast and expensive and super slow and cheap are the cache memories, named L1, L2, L3 in decre...