The Raku compiler throws errors of type
X::Syntax::Malformed when it knows what kind of declaration it is parsing, and encounters a syntax error, but can't give a more specific error message.
my Int a; # throws an X::Syntax::Malformed
===SORRY!===Malformed myat -e:1------> my Int ⏏a
method what(X::Syntax::Malformed: --> Str)
Returns a description of the thing that was being parsed.