=begin pod :kind("Type") :subkind("class") :category("exception")

=TITLE class X::Parameter::Placeholder

=SUBTITLE Compilation error due to an unallowed placeholder in a signature

    class X::Parameter::Placeholder does X::Comp { }

Thrown when a placeholder parameter is used inside a signature where
a normal parameter is expected. The reason is often that a named parameter
C<:$param> was misspelled as C<$:param>.

For example

=for code :skip-test<compile time error>
sub f($:param) { }

dies with

=for code :lang<text>
===SORRY!===
In signature parameter, placeholder variables like $:param are illegal
you probably meant a named parameter: ':$param'

=head1 Methods

=head2 method parameter

The text of the offensive parameter declaration (C<$:param> in the example
above).

=head2 method right

Suggestion on how to write the parameter declaration instead (C<:$param> in
the example above).


=end pod
