ike EBNF, PEG is a formal grammar for describing a formal language in terms
        of a set of rules used to recognize strings of this language. Unlike EBNF,
        PEGs have an exact interpretation. There is only one valid parse tree (see
        Abstract Syntax Tree) for each PEG grammar.
      </p>
<h5>
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        <span class="phrase"><a name="spirit.abstracts.parsing_expression_grammar.sequences"></a></span><a class="link" href="parsing_expres