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Java: is there a map function?
...m(Collection<E>, Function<E,E2>)
method provides the functionality you require.
Example:
// example, converts a collection of integers to their
// hexadecimal string representations
final Collection<Integer> input = Arrays.asList(10, 20, 30, 40, 50);
final Collection<String>...
How do I make a column unique and index it in a Ruby on Rails migration?
...umn unique in Ruby on Rails migration script. What is the best way to do it? Also is there a way to index a column in a table?
...
Return first N key:value pairs from dict
...ch keys were inserted first.
You can get any n key-value pairs though:
n_items = take(n, d.iteritems())
This uses the implementation of take from the itertools recipes:
from itertools import islice
def take(n, iterable):
"Return first n items of the iterable as a list"
return list(isli...
How to find index of all occurrences of element in array?
...arameter that specifies the index to start searching from, so you can call it in a loop to find all instances of a particular value:
function getAllIndexes(arr, val) {
var indexes = [], i = -1;
while ((i = arr.indexOf(val, i+1)) != -1){
indexes.push(i);
}
return indexes;
}
v...
What is the email subject length limit?
... had a scan of The RFC for email but could not see specifically how long it was allowed to be.
I have a colleague that wants to programmatically validate for it.
...
What are carriage return, linefeed, and form feed?
...
Carriage return means to return to the beginning of the current line without advancing downward. The name comes from a printer's carriage, as monitors were rare when the name was coined. This is commonly escaped as \r, abbreviated CR, and has ASCII value 13 or 0x0D.
Linefeed means to advance...
Vagrant ssh authentication failure
The problem with ssh authentication:
29 Answers
29
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Create an empty object in JavaScript with {} or new Object()?
...
Objects
There is no benefit to using new Object(); - whereas {}; can make your code more compact, and more readable.
For defining empty objects they're technically the same. The {} syntax is shorter, neater (less Java-ish), and allows you to instan...
findViewById in Fragment
...ragment. However, the findViewById method only works if I extend an Activity class. Is there anyway of which I can use it in Fragment as well?
...
Can one AngularJS controller call another?
Is it possible to have one controller use another?
14 Answers
14
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