I can't test it but I would start with:


atom ::= string
       | number
       | symbol

number ::= SIGN? DIGITS action => Sexp::Tiny::Actions::do_join
SIGN           ~ "+" | "-"
DIGITS         ~ [0-9]

# Exclude the new starting characters for numbers from the "symbol" ch
+aracter class
SYMCHAR ~ [^()\s"0-9+-]

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In reply to Re: S-expressions with Marpa::R2: Grammar for Numbers by Corion
in thread S-expressions with Marpa::R2: Grammar for Numbers by karlgoethebier

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