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How to get a string after a specific substring?
...("world",1)[1]
split takes the word(or character) to split on and optionally a limit to the number of splits.
In this example split on "world" and limit it to only one split.
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Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
Java Security: Illegal key size or default parameters?
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Most likely you don't have the unlimited strength file installed now.
You may need to download this file:
Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files 6
Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files 7 Download
Ja...
What is a memory fence?
...ead/writes occur in the order you expect. For example a 'full fence' means all read/writes before the fence are comitted before those after the fence.
Note memory fences are a hardware concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemen...
Using PHP with Socket.io
...t there are some ways to implement WebSockets. There is this jQuery plugin allowing you to use Websockets while gracefully degrading for non-supporting browsers. On the PHP side, there is this class which seems to be the most widely used for PHP WS servers.
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How to get the concrete class name as a string? [duplicate]
...
instance.__class__.__name__
example:
>>> class A():
pass
>>> a = A()
>>> a.__class__.__name__
'A'
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Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;
...ing the Java Build Path and seeing this new item, and unchecking the originally-included support library solved the problem for me.
– Tom Pace
Sep 26 '13 at 17:20
9
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How to sort a list in Scala by two fields?
... @SachinK: You could implement customOrdering as Ordering[Row] manually or using Ordering.by like this: val customOrdering = Ordering.by((r: Row) => (r.lastName, r.firstName))( Ordering.Tuple2(Ordering.String.reverse, Ordering.String) )`
– senia
Jun ...
How to go about formatting 1200 to 1.2k in java
...ng, String> suffixes = new TreeMap<> ();
static {
suffixes.put(1_000L, "k");
suffixes.put(1_000_000L, "M");
suffixes.put(1_000_000_000L, "G");
suffixes.put(1_000_000_000_000L, "T");
suffixes.put(1_000_000_000_000_000L, "P");
suffixes.put(1_000_000_000_000_000_000L, "E");
}
publ...
How do I get current date/time on the Windows command line in a suitable format for usage in a file/
Update: Now that it's 2016 I'd use PowerShell for this unless there's a really compelling backwards-compatible reason for it, particularly because of the regional settings issue with using date . See @npocmaka's https://stackoverflow.com/a/19799236/8479
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