Untitled Document

```
E ::= E "+" F | E "-" F | F
F ::= F "*" F | G
G ::= "-"G | H
H ::= N | Id | "(" E ")"
```
a) x * (y--5) : unambiguous
b) +x * y : cannot be generated
c) x * y + z * v : unambiguous
d) (x + z) * -u * (v) : ambiguous
e) -(-(x + y)) : unambiguous

 senv[f:t1->t2][g:t3->t4][x:t1] |- Ef:t2
 senv[f:t1->t2][g:t3->t4][y:t3] |- Eg:t4    senv[f:t1->t2][g:t3->t4] |- e:t
----------------------------------------------------------------------------
              let f(x:t1):t2 = Ef;  g(y:t3):t4 = Eg in e : t

a) bool
b) no type
c) int
d) bool
a) 0 7 1 43
b) 0 7 0 7
c) 43 7 43 7
d) 43 7 1 43
a) procedures can only reference their parameters and local variables: yes
b) dynamic typig: no
c) static scoping: no
d) only call-by-value parameter passing: no
e) no recursive functions: yes
f) no nested procedure declarations: yes
g) static typing: no
h) no overloading of procedure names: no
i) dynamic scoping: yes
j) recursive procedure names: yes