The GO programming language syntax is specified using Extended Backus-Naur Form (EBNF) :
* Production = production_name "=" [ Expression ]
* Expression = Alternative { "l" Alternative }
* Alternative = Term { Term }
* Term = Production_name l token [ "?"token] l Group l Option l Repetition
* Group = " ( "" Expression")"
* Option = " [ " Expression "" ]"
* Repetition = " {" Expression "}"
