| `50` | `fetch_token` | `index` | Returns the token at this index. The token data is stored in an array in a format described below.
| `51` | `fetch_param` | `index` | Returns the script param at this index.
| `52` | `fetch_store` | `index` | Returns the transaction storage at this index.
| | | |
| | | | **Cryptography**
| `60` | `hash` | `algorithm``message` | Returns the hash of `message` with given algorithm. *An unknown hashing algorithm make the whole script returns true, allowing new hashing algorithms via soft-forks.*
| `61` | `verify_sig` | `message``sig``key` | Verify if `sig` is valid for the `message` and public `key`. *If `sig` and `key` "cryptographic system codes" are equal but undefined, the function returns true to allow new cryptographic systems via soft-forks.*
> Any undeclared system function makes the script valid without executing it, allowing addition of