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What is the colon operator in Ruby?
..." # false
:foo.equal? :foo # true
This makes comparing two symbols really fast (since only a pointer comparison is involved, as opposed to comparing all the characters like you would in a string), plus you won't have a zillion copies of the same symbol floating about.
Also, unlike strings, sy...
Copy data into another table
...the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema):
INSERT INTO newTable (col1, col2, col3)
SELECT column1, column2, column3
FROM oldTable
...
How to fix Python indentation
...py script that you find in the Tools/scripts/ directory of your Python installation:
Change Python (.py) files to use
4-space indents and no hard tab
characters. Also trim excess spaces
and tabs from ends of lines, and
remove empty lines at the end of
files. Also ensure the last line ...
CodeIgniter: Create new helper?
...o it.
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
if ( ! function_exists('test_method'))
{
function test_method($var = '')
{
return $var;
}
}
Save this to application/helpers/ . We shall call it "new_helper.php"
The first line exists to ...
Executing elements inserted with .innerHTML
...ad via src. The above script can be changed to check elem.src and conditionally set the src property of the created script element instead of setting its text content.
– Ryan Morlok
Nov 9 '15 at 15:27
...
C# Regex for Guid
...{12}[)}]?$",
"'$0'");
This matches the following styles, which are all equivalent and acceptable formats for a GUID.
ca761232ed4211cebacd00aa0057b223
CA761232-ED42-11CE-BACD-00AA0057B223
{CA761232-ED42-11CE-BACD-00AA0057B223}
(CA761232-ED42-11CE-BACD-00AA0057B223)
Update 1
@NonStatic mak...
Where is Vagrant saving changes to the VM?
...omething like "D:\VHDs\VBox\" and there I found my vagrant test vm: "test01_1347456065". It was called test01, so I guess vagrant adds the numbers to keep things unique.
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...
Limits of Nat type in Shapeless
...a> Nat(3)
res10: shapeless.Succ[shapeless.Succ[shapeless.Succ[shapeless._0]]] = Succ()
So to represent the number 1000000, you would have a type that is nested 1000000 levels deep, which would definitely blow up the scala compiler. The current limit seems to be about 400 from experimentation, b...
How should I validate an e-mail address?
...ache.commons.validator.routines.EmailValidator)
(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:25[0-...
How to determine the longest increasing subsequence using dynamic programming?
...ence) which is ending at element with index i. To compute DP[i] we look at all indices j < i and check both if DP[j] + 1 > DP[i] and array[j] < array[i] (we want it to be increasing). If this is true we can update the current optimum for DP[i]. To find the global optimum for the array you c...