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How to tell if browser/tab is active [duplicate]
...depends on a mouse move. if the tab was entered using a keyboard shortcut, then the hover is probably not triggered.
– Kae Verens
Jan 4 '13 at 20:39
add a comment
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How to break out of a loop in Bash?
...that different in bash.
done=0
while : ; do
...
if [ "$done" -ne 0 ]; then
break
fi
done
: is the no-op command; its exit status is always 0, so the loop runs until done is given a non-zero value.
There are many ways you could set and test the value of done in order to exit the loo...
Custom exception type
...ant: integers, strings, objects, whatever. If you want to throw an object, then simply create a new object, just as you would create one under other circumstances, and then throw it. Mozilla's Javascript reference has several examples.
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Applying a function to every row of a table using dplyr?
...t is longer than length 1 either as a vector or as a data.frame with rows, then it matters whether we use rows or cols for .collate:
mtcars[1:2] %>% by_row(function(x) 1:5)
mtcars[1:2] %>% by_row(function(x) 1:5, .collate = "rows")
mtcars[1:2] %>% by_row(function(x) 1:5, .collate = "cols")...
Tab key == 4 spaces and auto-indent after curly braces in Vim
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If you have expandtab set then it should be using spaces. Do you also "set compatible"? That has various side effects including resetting expandtab to its default of "off"
– Ken
Dec 4 '08 at 14:59
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jquery UI dialog: how to initialize without a title bar?
...If you have some other event that triggers the close method of the dialog, then there can be cases where you don't need the close button on the title bar.
– Carlos Pinto
Dec 9 '11 at 20:06
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How can I see the SQL that will be generated by a given ActiveRecord query in Ruby on Rails
...query_object.class somewhere to see what type of object your working with, then lookup the docs.
For example, in Rails 3.0, scopes use ActiveRecord::Relation which has a #to_sql method. For example:
class Contact < ActiveRecord::Base
scope :frequently_contacted, where('messages_count > 10...
http HEAD vs GET performance
... @aalaap If you are going to update a view counter for HEAD requests, then you should do so for GET requests also. The decision to use GET or HEAD is ultimately up to the HTTP client. Your server should behave the same way for both request types, except there is no response body when responding...
Cloning a MySQL database on the same MySql instance
...ate new_db by using standard mysql command: "CREATE DATABASE new_db;" and then used these commands: mysqldump -u root -p old_db | mysql -u root -p new_db
– valentt
Jun 23 '14 at 23:27
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Extract filename and extension in Bash
...here's a caveat in that if your filename was of the form ./somefile.tar.gz then echo ${FILENAME%%.*} would greedily remove the longest match to the . and you'd have the empty string.
(You can work around that with a temporary variable:
FULL_FILENAME=$FILENAME
FILENAME=${FULL_FILENAME##*/}
echo ${...