Perl syntax nuances

Because of incremental nature of IDEA lexer and Perl's heavy context dependency, there are few nuances in Perl syntax for Camelcade plugin:

• After initial project indexing, some package subs calls, like Foo::bar may be incorrectly recognized as package names. Hitting enter (causes re-lexing) should solve the problem.
• In constructions like (grep | map | sort) { ... } (/regex/ | <handle>) you should help lexer to recognize regex or handle reading. Use m/regex/ to force regex proper parsing and use enclosing parentheses for filehandle reading: (<handle>)
• our variables should be declared at least once. You may refer them later as $package::var, but to make re-factoring works properly you must declare them somewhere.
• Try to avoid using 'fancy' method calls method Foo::Bar. Use canonical Foo::Bar->method. Fancy usage is supported, but may be glitchy.
• If your project contains XS subs, declare them with prototypes in pure Perl. Plugin may find such declarations and has no any access to XS parts.
• Braces symbols in regex MUST be escaped. /\p{Word}/ is ok, but /foo{/ is not. Perl recommends to do it but it's not required. Camelcade requires escaping.
• Currently only ascii identifiers are supported, you can't use non-ascii symbols in identifiers (TBF).