Notation for reasoning about parsing - described in its own notation

gistfile1.txt

    whitespace { optional }:
        whitespace?
        token("whitespace")
        select(
            token("?") as optional
            token("!") as !optional
        )
        whitespace?

    parameter { name, args, value }:
        whitespace?
        until_whitespace_or_any("{") as name
        whitespace?
        token("{")
        whitespace?
        while(!token("}"))
            whitespace?
            until_whitespace_or_any(",").push_to(args)
            whitespace?
        ?(
            whitespace!
            token("as")
            whitespace!
            until_whitespace as value
        )
        whitespace?
        token(":")
        whitespace?
        new_line
        select(
            tab_indent
            point_to(parameter, "This parameter lacks a body")
        )

    token { text_value, inverted, predicate }:
        token("token")
        whitespace?
        token("(")
        whitespace?
        text as text_value
        whitespace?
        token(")")
        ?(
            whitespace!
            token("as")
            whitespace!
            token("!") as inverted
            until_whitespace as predicate
        )
        whitespace?

    select { args }:
        whitespace?
        token("select")
        whitespace?
        token("(")
        new_line
        while(!token(")"))
            whitespace?
            whole_line.push_to(args)
            new_line

    optional { args }:
        whitespace?
        token("?")
        whitespace?
        token("(")
        new_line
        while(!token(")"))
            whitespace?
            whole_line.push_to(args)
            new_line

    until_whitespace { predicate }:
        whitespace?
        token("until_whitespace")
        ?(
            whitespace!
            token("as")
            whitespace!
            until_whitespace as predicate
        )
        whitespace?

    until_whitespace_or_any { text_value, predicate, push_value }:
        whitespace?
        token("until_whitespace_or_any")
        whitespace?
        token("(")
        whitespace?
        text as text_value
        whitespace?
        token(")")
        select(
            predicate { value } as predicate:
                whitespace!
                token("as")
                whitespace!
                until_whitespace as value
            push_value { value } as push_value:
                token(".push_to")
                whitespace?
                token("(")
                whitespace?
                until_whitespace as value
                whitespace?
                token(")")
        )
        whitespace?

    new_line { }:
        whitespace?
        token("new_line")
        whitespace?

    tab_indent { }:
        whitespace?
        token("tab_indent")
        whitespace?

    point_to { part, error_message }:
        whitespace?
        token("point_to")
        whitespace?
        token("(")
        until_whitespace_or_any(",") as part
        whitespace?
        token(",")
        whitespace?
        text as error_message
        whitespace?
        token(")")
        whitespace?

    text { value }:
        whitespace?
        token("text")
        whitespace!
        token("as")
        whitespace!
        until_whitespace as value
        whitespace?

    while { end_token }:
        whitespace?
        token("while")
        whitespace?
        token("(")
        whitespace?
        token("!token")
        whitespace?
        token("(")
        whitespace?
        text as end_token
        whitespace?
        token(")")
        whitespace?
        new_line
        select(
            tab_indent
            point_to(while, "This while block lacks a body")
        )

    whole_line { push_value }:
        whitespace?
        token("whole_line.push_to")
        whitespace?
        token("(")
        whitespace?
        until_whitespace as push_value
        whitespace?
        token(")")
        whitespace?