# Grammar: Token

    # token: never backtracks by default (can be overridden)

    token proper_name { <word>+ <space> <word>+ }

    # Which is short for:

    regex name :ratchet { ... }

# regex: use the colon to specify no backtracking

regex proper_name { +: +: }

In normal regexes, use *:, +:, or ?: to prevent backtracking into

the quantifier. If you want to backtrack, append either a ? or a !

to the quantifier. The ? forces frugal matching as usual, while

the ! forces greedy matching.