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How to change a nullable column to not nullable in a Rails migration?
I created a date column in a previous migration and set it to be nullable. Now I want to change it to be not nullable. How do I go about doing this assuming there are null rows in that database? I'm ok with setting those columns to Time.now if they're currently null.
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Logging uncaught exceptions in Python
...d pointed out, sys.excepthook is invoked every time an exception is raised and uncaught. The practical implication of this is that in your code you can override the default behavior of sys.excepthook to do whatever you want (including using logging.exception).
As a straw man example:
>>> i...
Replace whole line containing a string using Sed
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You can use the change command to replace the entire line, and the -i flag to make the changes in-place. For example, using GNU sed:
sed -i '/TEXT_TO_BE_REPLACED/c\This line is removed by the admin.' /tmp/foo
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Self-references in object literals / initializers
...To complete my above statement, since foo is beeing declared as a variable and c will only be evaluated at the time it is invoked, using foo inside c will work, as opposed to this (be careful though)
– Bernardo Dal Corno
Apr 19 '18 at 20:11
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How to test equality of Swift enums with associated values
...from Swift 4.1 (due to SE-0185, Swift also supports synthesizing Equatable and Hashable for enums with associated values.
So if you're on Swift 4.1 or newer, the following will automatically synthesize the necessary methods such that XCTAssert(t1 == t2) works. The key is to add the Equatable protoc...
Removing viewcontrollers from navigation stack
...a navigation stack, with say 5 UIViewControllers. I want to remove the 3rd and 4th viewcontrollers in the stack on the click of a button in the 5th viewcontroller. Is it possible to do this? If so how?
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Adjust UILabel height to text
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I've just put this in a playground and it works for me.
Updated for Swift 4.0
import UIKit
func heightForView(text:String, font:UIFont, width:CGFloat) -> CGFloat{
let label:UILabel = UILabel(frame: CGRectMake(0, 0, width, CGFloat.greatestFiniteMagn...
Default height for section header in UITableView
...hmm.. As for me UITableViewAutomaticDimension returns -1 (hardcoded const) and I don't see any sections at all in my UITableView.
– skywinder
Sep 22 '13 at 21:17
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Why do my list item bullets overlap floating elements
... +1: Great CSS, I searched like a crazy for a GOOD VERSATILE soltuion and here it is on SO. The only small draw back is that zoom property does not validate CSS, but I tested and on IE7, IE8 is not necessary, so it's probably just for IE6.
– Marco Demaio
A...
Convert a date format in PHP
... in SQL); however I don't know how the date function requires a timestamp, and I can't get a timestamp from this string.
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