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[mypyc] Report an error for async generator expressions - #22247
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An async generator expression (one that uses 'async for' or 'await') was compiled into a list and a regular iterator over it, which can't be used with 'async for', so using the result always failed at runtime. Report a compile error instead, since async generators aren't supported. An 'await' in the first iterable is fine, since it's evaluated in the enclosing function.
p-sawicki
approved these changes
Oct 21, 2026
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An async generator expression (one that uses 'async for' or 'await') was compiled into a list and a regular iterator over it, which can't be used with 'async for', so using the result always failed at runtime. Report a compile error instead, since async generators aren't supported.
An 'await' in the first iterable is fine, since it's evaluated in the enclosing function.