LALR Parser Generator

for example, code

if (true) :
  if (true)
        ;
elseif (true) :

endif;

and code

if (true) :
    if (true)
        ;
    else
        ;
elseif (true) :

endif;

should both valid, but php.exe is unable to parse the first one, the grammar is conflict on 'elseif' and it using wrong shift, you have to lookahead for ':' token.