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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?
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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 imported library to avoid name collisions. (as was reused to do different things to avoid needing extra keywords.)
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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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