state declares a lexically scoped variable, just like
However, those variables will never be reinitialized, contrary to
lexical variables that are reinitialized each time their enclosing block
See Persistent Private Variables in perlsub for details.
If more than one variable is listed, the list must be placed in
parentheses. With a parenthesised list,
undef can be used as a
dummy placeholder. However, since initialization of state variables in
list context is currently not possible this would serve no purpose.