Documentation for method positional assembled from the following types:

class Parameter

From Parameter

(Parameter) method positional

Defined as:

method positional(Parameter:D: --> Bool:D)

Returns True if the parameter is positional.

my Signature $sig = :(Str $x, Bool :$is-named);
say $sig.params[0].positional;                     # OUTPUT: «True␤» 
say $sig.params[1].positional;                     # OUTPUT: «False␤»