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Postfix Self Expression
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Postfix Self Expression
A postfix
self
expression consists of an expression or the name of a type, immediately followed by
.self
. It has the following forms:
-
expression.self
-
type.self
The first form evaluates to the value of the
expression
. For example,
x.self
evaluates to
x
.
The second form evaluates to the value of the
type
. Use this form to access a type as a value. For example, because
SomeClass.self
evaluates to the
SomeClass
type itself, you can pass it to a function or method that accepts a type-level argument.
GRAMMAR OF A SELF EXPRESSION
postfix-self-expression → postfix-expression
.
self
https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/swift/grammar/postfix-self-expression
