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java: HashMap not working
...s aren't retained at runtime. They are just "syntactic sugar" for explicit casting to save you doing this:
Integer i = (Integer)myMap.get("foo");
To give you an example, this code is perfectly legal:
Map<String, Integer> myMap = new HashMap<String, Integer>();
Map<Integer, String&...
How to pass a single object[] to a params object[]
...
A simple typecast will ensure the compiler knows what you mean in this case.
Foo((object)new object[]{ (object)"1", (object)"2" }));
As an array is a subtype of object, this all works out. Bit of an odd solution though, I'll agree.
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Using isKindOfClass with Swift
...nted out in @Kevin's answer, the correct way would be to use optional type cast operator as?. You can read more about it on the section Optional Chaining sub section Downcasting.
Edit 2
As pointed on the other answer by user @KPM, using the is operator is the right way to do it.
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Concatenate multiple result rows of one column into one, group by another column [duplicate]
...ase.
string_agg() expects data type text as input. Other types need to be cast explicitly (actor::text) - unless an implicit cast to text is defined - which is the case for all other character types (varchar, character, "char"), and some other types.
As isapir commented, you can add an ORDER BY c...
Type definition in object literal in TypeScript
... The DRY (Don't Repeat Yourself) option by @Rick Love with the cast operator seems mucho neater. Just commenting, not downvoting...
– spechter
Nov 17 '17 at 0:43
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How do I make the return type of a method generic?
...e]);
}
Option 2: When you don't want to use fancy methods of conversion - Cast the value to object and then to generic type.
public static T ConfigSetting<T>(string settingName)
{
return (T)(object)ConfigurationManager.AppSettings[settingName];
}
Note - This will throw an error if t...
How to alter a column's data type in a PostgreSQL table?
... For some other cases, you might need to specify the way to cast like ALTER TABLE tbl_name ALTER COLUMN col_name TYPE integer USING col_name::integer;
– Nobu
May 1 '14 at 17:45
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Double negation (!!) in javascript - what is the purpose? [duplicate]
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It casts to boolean. The first ! negates it once, converting values like so:
undefined to true
null to true
+0 to true
-0 to true
'' to true
NaN to true
false to true
All other expressions to false
Then the other ! negates i...
Change default primary key in Eloquent
...d to make sure you set public $incrementing = false otherwise laravel will cast the field to an Integer, giving 0
class User extends Model {
protected $primaryKey = 'my_string_key';
public $incrementing = false;
}
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How to set enum to null
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@equiman no need to cast since the type is specified on the left, you are basically duplicating the first part of my answer that is already accepted.
– Rodney S. Foley
Jul 8 '15 at 22:50
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