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How to name variables on the fly?
...# 4 4.6 3.1 1.5 0.2 setosa
# 5 5.0 3.6 1.4 0.2 setosa
# 6 5.4 3.9 1.7 0.4 setosa
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Ignoring a class property in Entity Framework 4.1 Code First
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As of EF 5.0, you need to include the System.ComponentModel.DataAnnotations.Schema namespace.
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Rails 4: before_filter vs. before_action
... before_filter.
However all before_filters syntax are deprecated in Rails 5.0 and will be removed in Rails 5.1
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Run a callback only if an attribute has changed in Rails
...e_to_<attribute>?
<attribute>_before_last_save
Rails <= 5.0
class Page < ActiveRecord::Base
before_save :do_something, if: :status_id_changed?
private
def do_something
# ...
end
end
This utilizes the fact that the before_save callback can conditionally execute ...
Using jQuery To Get Size of Viewport
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I tested this on Windows IE6, IE8, FF3.6.3, Google Chrome 5.0.375.70, Opera 10.53, and Safari 5.0 (7533.16). This works consistently on all of these. I also tested FF3.6.3 on Ubuntu and it works there too. I think I'm using jQuery 1.3 with WordPress 2.9.2, which is where I needed th...
NSUserDefaults removeObjectForKey vs. setObject:nil
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Swift 5.0 + iOS 11 and up
Both methods remove the value. Tried this in a playground:
import Foundation
let key = "Test"
let value = "test"
let defaults = UserDefaults.standard
func printUD() {
print("UserDefaults after modi...
Which MySQL data type to use for storing boolean values
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For MySQL 5.0.3 and higher, you can use BIT. The manual says:
As of MySQL 5.0.3, the BIT data type is used to store bit-field
values. A type of BIT(M) enables storage of M-bit values. M can range
from 1 to 64.
Otherwise, according to...
Converting file size in bytes to human-readable string
...d(dp) + ' ' + units[u];
}
console.log(humanFileSize(5000, true)) // 5.0 kB
console.log(humanFileSize(5000, false)) // 4.9 KiB
console.log(humanFileSize(-10000000000000000000000000000)) // -8271.8 YiB
console.log(humanFileSize(999949, true)) // 999.9 kB
console.log(humanFileSize(999950,...
How to declare or mark a Java method as deprecated?
... both!
Quoting the java documentation on this subject:
Starting with J2SE 5.0, you deprecate a class, method, or field by using the @Deprecated annotation. Additionally, you can use the @deprecated Javadoc tag tell developers what to use instead.
Using the annotation causes the Java compiler to gen...
SQL Client for Mac OS X that works with MS SQL Server [closed]
...lso offers an MSSQL JDBC driver. Install sqljdbc4.jar (sqljdbc.jar for JRE 5.0) somewhere you keep Java packages (such as ~/Library/Java or /Library/Java/Extensions). Whichever driver you pick, make sure you add it to the "Extra Class Path" list for the MSSQL driver, then pick the class name for the...