$ perl -wE 'sub meth { return (@_, q{A}); } my $o = bless {}; my $x = q{meth}; say $o->$x;'
main=HASH(0x10053ad8)A

$ perl -wE 'sub meth { return (@_, q{A}); } my $o = bless {}; my %x = (a => q{meth}); say $o->$x{a};'
syntax error at -e line 1, near "$x{a"
Execution of -e aborted due to compilation errors.

$ perl -wE 'sub meth { return (@_, q{A}); } my $o = bless {}; my %x = (a => q{meth}); say $o->{ $x{a} };'
Use of uninitialized value in say at -e line 1.

$ perl -wE 'sub meth { return (@_, q{A}); } my $o = bless {}; my %x = (a => q{meth}); say $o->${\$x{a}};'
main=HASH(0x10053ad8)A