package MyAwesomeDSL;

use Sub::Info;

sub define_blabla {
  ...
}

sub define_something (&;) {
  my ($coderef) = @_;

  my $info = sub_info($coderef);

  local *{$info->{package} . '::define_blabla' } = \&define_blabla;

  $coderef->();

}

package main;


use MyAwesomeDSL;


define_something {
  define_blabla(...);
};

1;