empty_interpolation: 'clown%{}shoe'
escaped_empty_interpolation: 'clown%%{}{shoe}s'
only_empty_interpolation: '%{}'
empty_namespace: '%{::}'
whitespace1: '%{ :: }'
whitespace2: '%{   }'

quoted_empty_interpolation: 'clown%{""}shoe'
quoted_escaped_empty_interpolation: 'clown%%{""}{shoe}s'
quoted_only_empty_interpolation: '%{""}'
quoted_empty_namespace: '%{"::"}'
quoted_whitespace1: '%{ "::" }'
quoted_whitespace2: '%{ "" }'