python runtime_error ai_generated true

RuntimeError: cannot reuse already awaited coroutine

ID: python/asyncio-cannot-reuse-already-awaited-coroutine

Also available as: JSON · Markdown · 中文
80%Fix Rate
90%Confidence
0Evidence
2024-04-19First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
3.8+ active — — —
3.9+ active — — —
3.10+ active — — —
3.11+ active — — —
3.12+ active — — —

Root Cause

A coroutine object was awaited once and then awaited again. Coroutine objects are single-use; each call to a coroutine function yields a fresh coroutine.

generic

中文

协程对象被 await 一次后再次 await。协程对象只能使用一次；每次调用协程函数都会产生新的协程。

Workarounds

  1. 97% success 
    # Wrong
c = fetch(url)
await c
await c
# Right
await fetch(url)
await fetch(url)
  2. 92% success 
    task = asyncio.create_task(fetch(url))
await task
await task  # Tasks are awaitable multiple times

Dead Ends

Common approaches that don't work:

  1. 95% fail

    The coroutine state is exhausted; send raises StopIteration immediately.

  2. 90% fail

    The coroutine object is already closed; ensure_future raises the same error.