class X::Syntax::Perl5Var does X::Syntax { }

Syntax error thrown when some piece of code tries to use one of the old Perl variables (and it does not error for some other reason).

say $];

dies with

Unsupported use of $] variablein Raku please use $*RAKU.version or $*RAKU.compiler.version

For every unsupported variable (which include most $^'letter' constructs, as well as others like $", the error message will mention that the variable is unsupported and the equivalent commands you could use.

Typegraph§

Type relations for X::Syntax::Perl5Var
raku-type-graph X::Syntax::Perl5Var X::Syntax::Perl5Var Exception Exception X::Syntax::Perl5Var->Exception X::Syntax X::Syntax X::Syntax::Perl5Var->X::Syntax Mu Mu Any Any Any->Mu Exception->Any X::Comp X::Comp X::Comp->Exception X::Syntax->Exception X::Syntax->X::Comp

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