perldoc -f my
my EXPR
my TYPE EXPR
my EXPR : ATTRS
my TYPE EXPR : ATTRS
A "my" declares the listed variables to be local (lexically) t
+o
the enclosing block, file, or "eval". If more than one value i
+s
listed, the list must be placed in parentheses.
The exact semantics and interface of TYPE and ATTRS are still
evolving. TYPE is currently bound to the use of "fields" pragm
+a,
and attributes are handled using the "attributes" pragma, or
starting from Perl 5.8.0 also via the "Attribute::Handlers"
module. See "Private Variables via my()" in perlsub for detail
+s,
and fields, attributes, and Attribute::Handlers.