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How to get the original value of an attribute in Rails
...
Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should ap...
“Auto Layout still required after executing -layoutSubviews” with UITableViewCell subclass
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I encountered the same problem while manually adding constraints in code. In code, I was doing the following:
{
[self setTranslatesAutoresizingMaskIntoConstraints:YES];
[self addSubview:someView];
[self addSubview:someOtherView];
[self addConstraint...
Is there a read-only generic dictionary available in .NET?
...lt;TKey, TValue>
{
private readonly IDictionary<TKey, TValue> _dictionary;
public ReadOnlyDictionary()
{
_dictionary = new Dictionary<TKey, TValue>();
}
public ReadOnlyDictionary(IDictionary<TKey, TValue> dictionary)
{
_dictionary = dict...
How to remove part of a string? [closed]
...
If you're specifically targetting "11223344", then use str_replace:
// str_replace($search, $replace, $subject)
echo str_replace("11223344", "","REGISTER 11223344 here");
...
How do I break a string over multiple lines?
...se "..." if you need to split lines in the middle of words or want to literally type linebreaks as \n:
key: "Antidisestab\
lishmentarianism.\n\nGet on it."
YAML is crazy.
Block scalar styles (>, |)
These allow characters such as \ and " without escaping, and add a new line (\n) to the end o...
How to merge lists into a list of tuples?
...
In Python 2:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> zip(list_a, list_b)
[(1, 5), (2, 6), (3, 7), (4, 8)]
In Python 3:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> list(zi...
How JavaScript closures are garbage collected
...e expected behavior.
From Mozilla's Memory management page: "As of 2012, all modern browsers ship a mark-and-sweep garbage-collector." "Limitation: objects need to be made explicitly unreachable".
In your examples where it fails some is still reachable in the closure. I tried two ways to make it...
Getting the class name from a static method in Java
...tatic context to mean the current Class in Java, that that "class.xxx" was allowed in either instance or static code to mean this class! The problem with this is that MyClass is verbose and redundant, in the context. But then as much as I like Java it does seem to lean towards verbosity.
...
iPhone Data Usage Tracking/Monitoring
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The thing is that pdp_ip0 is one of interfaces, all pdpXXX are WWAN interfaces dedicated to different functions, voicemail, general networking interface.
I read in Apple forum that :
The OS does not keep network statistics on a process-by-process basis. As such, there's n...
How can I repeat a character in Bash?
...ay matter with large repeat counts).
Summary:
If your repeat count is small, say up to around 100, it's worth going with the Bash-only solutions, as the startup cost of external utilities matters, especially Perl's.
Pragmatically speaking, however, if you only need one instance of repeating ch...