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ABNF Parser Generator

Expressions

This is a demonstration of the conversion of a grammar from left-recursive to non-left-recursive. It is the non-left-recursive variant of the expressions grammar found on page 193 of the ref. 2.

ABNF Grammar:   X

Expressions Input

For a clear demonstration of how the empty string terms come into play,

  • Click Configuration
  • Check "Save Parsed Phrases"
  • Click Parse
  • Select "Tprime" (or "Eprime") from the drop down box below
  • Click "Parsed Phrases"
Input String:   X

Parser Output: