| INT (EInt INT, (INTleft, INTright))
| STRING (EString STRING, (STRINGleft, STRINGright))
| LBRACK elist RBRACK (EList elist, (LBRACKleft, RBRACKright))
| LET exp IN exp END (ELocal (exp1, exp2), (LETleft, ENDright))
| SYMBOL (EVar SYMBOL, (SYMBOLleft, SYMBOLright))
| INT (EInt INT, (INTleft, INTright))
| STRING (EString STRING, (STRINGleft, STRINGright))
| LBRACK elist RBRACK (EList elist, (LBRACKleft, RBRACKright))
| LET exp IN exp END (ELocal (exp1, exp2), (LETleft, ENDright))
| SYMBOL (EVar SYMBOL, (SYMBOLleft, SYMBOLright))