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What is the purpose of willSet and didSet in Swift?
.... When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is modified without needing another field. For instance, in that example:
class Foo {
var myProperty: Int = 0 {
didSet {
print("The value of ...
Escape a string for a sed replace pattern
...o be escaped to get their special meaning. For example, if you escape a digit in the replacement string, it will turn in to a backreference.
As Ben Blank said, there are only three characters that need to be escaped in the replacement string (escapes themselves, forward slash for end of statement a...
How do you count the number of occurrences of a certain substring in a SQL varchar?
...
The first way that comes to mind is to do it indirectly by replacing the comma with an empty string and comparing the lengths
Declare @string varchar(1000)
Set @string = 'a,b,c,d'
select len(@string) - len(replace(@string, ',', ''))
...
Can I install Python windows packages into virtualenvs?
Virtualenv is great: it lets me keep a number of distinct Python installations so that different projects' dependencies aren't all thrown together into a common pile.
...
How to get distinct values for non-key column fields in Laravel?
This might be quite easy but have no idea how to.
12 Answers
12
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What is the difference between “git branch” and “git checkout -b”?
I used git checkout -b to create a new branch. I think that git branch does the same thing.
How do these two commands differ, if they differ at all?
...
How to turn NaN from parseInt into 0 for an empty string?
Is it possible somehow to return 0 instead of NaN when parsing values in JavaScript?
18 Answers
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jquery disable form submit on enter
... (keyCode === 13) {
e.preventDefault();
return false;
}
});
EDIT: missed it, it's better to use keyup instead of keypress
EDIT 2: As in some newer versions of Firefox the form submission is not prevented, it's safer to add the keypress event to the form as well. Also it doesn't work (a...
What is __gxx_personality_v0 for?
This is a second-hand question from an OS development site, but it made me curious since I couldn't find a decent explanation anywhere.
...
How can I add some small utility functions to my AngularJS application?
I would like to add some utility functions to my AngularJS application. For example:
7 Answers
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