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Swift - Cast Int into enum:Int
...on Jeffery Thomas's answer.
to be safe place a guard statement unwrap the cast before using it,
this will avoid crashes
@IBAction func selectFilter(sender: AnyObject) {
guard let filter = MyTimeFilter(rawValue: (sender as UIButton).tag) else {
return
}
timeFilterSelec...
Export specific rows from a PostgreSQL table as INSERT SQL script
...d line utility pg_dump to export to a file:
create table export_table as
select id, name, city
from nyummy.cimory
where city = 'tokyo'
$ pg_dump --table=export_table --data-only --column-inserts my_database > data.sql
--column-inserts will dump as insert commands with column names.
--data-...
Direct casting vs 'as' operator?
...
string s = (string)o; // 1
Throws InvalidCastException if o is not a string. Otherwise, assigns o to s, even if o is null.
string s = o as string; // 2
Assigns null to s if o is not a string or if o is null. For this reason, you cannot use it with value types (th...
Is it possible to solve the “A generic array of T is created for a varargs parameter” compiler warni
...
As you can see in Joseph Darcy's blog post, the Project Coin exercise to select some small incremental language improvements for Java 7 accepted Bob Lee's proposal to allow something like @SuppressWarnings("varargs") at the method side to make this warning go away in situations where it was known ...
Java Generics: Cannot cast List to List? [duplicate]
...
If you do have to cast from List<DataNode> to List<Tree>, and you know it is safe to do so, then an ugly way to achieve this is to do a double-cast:
List<DataNode> a1 = new ArrayList<DataNode>();
List<Tree> b1 =...
Conversion from Long to Double in Java
...ue() if you want to go via Long. Note this is the same, internally, as the cast from a double, except that you're doing some auto/unboxing.
– Joe Kearney
Sep 16 '10 at 8:27
...
Find index of a value in an array
... return -1;
}
And you can use LINQ as well:
int keyIndex = words
.Select((v, i) => new {Word = v, Index = i})
.FirstOrDefault(x => x.Word.IsKey)?.Index ?? -1;
share
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improve thi...
generate days from date range
...000 days, and could be extended to go as far back or forward as you wish.
select a.Date
from (
select curdate() - INTERVAL (a.a + (10 * b.a) + (100 * c.a) + (1000 * d.a) ) DAY as Date
from (select 0 as a union all select 1 union all select 2 union all select 3 union all select 4 union all ...
Finding the type of an object in C++
...
dynamic_cast should do the trick
TYPE& dynamic_cast<TYPE&> (object);
TYPE* dynamic_cast<TYPE*> (object);
The dynamic_cast keyword casts a datum from one pointer or reference type to another, performing a runtime ...
How to multiply duration by integer?
...stic type system (lack of operator overloading in this case) - you have to cast the multiplication to Duration * Duration = Duration, instead of the original one which actually makes more sense: Duration * int = Duration.
– Timmmm
Jan 5 '16 at 14:49
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