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Predicates

The predicates are identical to a parser generator or BNF description, since our sequence matching has very much in common to the logic behind a parser combinator. The predicates are inspired from pest.rs with the change that the operator shows as a prefix in our grammar.

Negation: !

The ! unnary/monadic operator signifies that the pattern described should not be matched, not progress the event chains and move on to check next pattern.

Repetition

Repetition syntaxMeaning
? <pattern>Optionally match pattern
\* <pattern>Match pattern zero or more times
+ <pattern>Match pattern one or more times
{n} <pattern>Match pattern exactly n times
{m,n} <pattern>Match pattern between m and n times
{,n} <pattern>Match pattern at most n times
{n,} <pattern>Match pattern at least n times