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This Expression

A this expression consists of the keyword this and refers to the implicit instance of the enclosing type that is being operated on in instance methods, subscripts, and initializers.

The type of this is This.

Mutability

If a [mutating] instance is being called, the argument for the implicit this parameter must be an l-value.

The argument expressions corresponding to any out or in out parameters of the callee must be l-values.

A call expression is never an l-value.