parser generator - Good BNF grammar tutorial / introduction for a beginner? -

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what's tip introduction bnf grammar (and how use them in practice)?

something concise many examples great. have been googling found enormously long artcles unclear examples far :/

(in particular case, i'm trying parse galaxy toolconfig syntax, includes if/else statements etc.)

i've found abnf rfc when regarding these issues: http://www.ietf.org/rfc/rfc2234.txt


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