Function in simulator
January 12, 2026 ยท View on GitHub
The following table describes built-in functions that will return tentative values. Will be updated when we find or implement a way to get accurate values.
| Function | Tentative Value/behavior |
|---|---|
| fastly.hash(key, seed, from, to) | Returns originally calculated hash string |
| h2.push(resource [, as]) | Ignore variadic arguments of "as" |
| resp.tarpit(interval_s [, chunk_size_bytes]) | No effect due to not support tarpitting |
| early_hints(resource [, resources...]) | No effect due to not support h2 and h3 |
| ratelimit.check_rate(entry, rc, delta, window, limit, pb, ttl) | Returns false due to no rate limiting support |
| ratelimit.check_rates(entry, rc1, delta1, window1, limit1, rc2, delta2, windows2, limit2, pb, ttl) | Returns false due to no rate limiting support |
| ratelimit.penaltybox_add(pb, entry, ttl) | No effect due to no rate limiting support |
| ratelimit.penaltybox_has(pb, entry) | Returns false due to no rate limiting support |
| ratelimit.ratecounter_increment(rc, entry, delta) | Returns 0 due to no rate limiting support |