============================================
Function calls
============================================

int main() {
  printf("hi! %d\n", x);
}

---

(function_declaration (identifier) (identifier) (formal_parameters)
  (statement_block
    (expression_statement (function_call (identifier) (string) (identifier)))))

============================================
Field access
============================================

int main() {
  s.data1;
  p->data2;
}

---

(function_declaration (identifier) (identifier) (formal_parameters)
  (statement_block
    (expression_statement (field_access (identifier) (identifier)))
    (expression_statement (deref_field_access (identifier) (identifier)))))

