I'm confused as to the uses of "as" keyword.
Is it a cast operator or alias operator ?
I encountered the following code on the internet which looked like a cast operator:
var list = json['images'] as List;
What does this mean?
2. as:- as operator is used to cast an object to a particular type if and only if when we are sure that the object is of that type. Example: Dart.
The new keyword is used to create an instance of a class. However, Dart 2 makes the new keyword optional. Calling a class will always return a new instance of that class.
No, it does not.
Dart supports == for equality and identical(a, b) for identity. Dart no longer supports the === syntax. Use == for equality when you want to check if too objects are "equal". You can implement the == method in your class to define what equality means.
as
means different things in different contexts.
It's primarily used as a type cast operator. From the Dart Language Tour:
as
: Typecast (also used to specify library prefixes)
It links to an explanation of how as
is also used to add a prefix to an import
ed library to avoid name collisions. (as
was reused to do different things to avoid needing extra keywords.)
just to add the as keyword is now flagged by the linter and they prefer you to use a check like is
if (pm is Person)
pm.firstName = 'Seth';
you can read more here https://github.com/dart-lang/linter/issues/145
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