used for reorganizing expression trees
| token | precedence |
|---|---|
| TOKEN_OR_IF | 1 |
| TOKEN_AND_IF | 2 |
| TOKEN_OR | 3 |
| TOKEN_EXOR | 4 |
| TOKEN_AND | 5 |
| TOKEN_EQ | 6 |
| TOKEN_NE | 6 |
| TOKEN_LT | 7 |
| TOKEN_GT | 7 |
| TOKEN_LE | 7 |
| TOKEN_GE | 7 |
| TOKEN_PLUS | 9 |
| TOKEN_MINUS | 9 |
| TOKEN_MUL | 10 |
| TOKEN_DIV | 10 |
| TOKEN_MOD | 10 |
| TOKEN_PAREN | 12 |
| TOKEN_STR | 99 |
to be filled