array of CaseStatement's
switch(condition)
array of unresolved GotoCaseStatement's
true if has default statement
true if has variable case values
last observed variable declaration in this statement
default:
set if in the 'finally' block of a TryFinallyStatement
set to TryCatchStatement or TryFinallyStatement if in _body portion
Do syntax copy of an array of Statement's.
Determine if an enclosed break would apply to this statement, such as if it is a loop or switch statement.
Determine if an enclosed continue would apply to this statement, such as if it is a loop statement.
Find last statement in a sequence of statements.
Support Visitor Pattern
Does this statement end with a return statement?
A cheaper method of doing downcasting of Statements.
https://dlang.org/spec/statement.html#switch-statement