Symbols

A Symbol objectrepresents an operator or identifier declared in a Dart program. Youmight never need to use symbols, but they’re invaluable for APIs thatrefer to identifiers by name, because minification changes identifiernames but not identifier symbols.

To get the symbol for an identifier, use a symbol literal, which is just# followed by the identifier:

#radix
#bar

Symbol literals are compile-time constants.