| 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
| 'if' exp optSemi 'then' exp optSemi 'else' exp
{% checkDoAndIfThenElse $2 $3 $5 $6 $8 >>
| 'let' binds 'in' exp { LL $ HsLet (unLoc $2) $4 }
| 'if' exp optSemi 'then' exp optSemi 'else' exp
{% checkDoAndIfThenElse $2 $3 $5 $6 $8 >>