/media/sda-magnetic/david/Dokumente-15/fernuni-hagen/cs-i-ii/old-cs-2-01/informatik2/bash-programming/lex-yacc-bash-etc/grammatik04.txt

statement   ::=         assignment | cond | loop
loop        ::=         while boolexpr do statement od
cond        ::=         if boolexpr then statement fi | if boolexpr then statement else statement fi
expr        ::=         numexpr | boolexpr
boolexpr    ::=         numexpr cop numexpr
numexpr     ::=         numexpr '+' term | term
term        ::=         term '*' factor | factor
factor      ::=         id | const | '(' numexpr ')'