.syntax aexp
aexp = as *as; as = /w+/ <'address ' $> ':=' ex1 <'store'> ';'; ex1 = ex2 *( '+' ex2 <'add'>
| '-' ex2 <'sub'>);
ex2 = ex3 *( '*' ex3 <'mpy'>
| '/' ex3 <'div'>);
ex3 = ex4 *('^' ex3 <'exp'>); ex4 = '+' ex5
| '-' ex5 <'minus'> | ex5;
ex5 = .id <'load' $>
| /\d+/ <'literal ' $> | '(' ex1 ')';
.end