perl6/doc/lib/X/Signature/Placeholder

(title)  class X::Signature::Placeholder

    class X::Signature::Placeholder does X::Comp

Compile time error thrown when a block has both an explicit signature and placeholder parameters. For example

    sub f() { $^x }

dies with

    ===SORRY!===
    Placeholder variable '$^x' cannot override existing signature

Methods

(head2)  placeholder

    method placeholder() returns Str:D

Returns the name of a placeholder that was used in a block that already had a signature.