pytorch/torch/fx/annotate.py
James Reed 538647fe1f [WIP][FX] BC guarantees for 1.10 (#63888)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/63888

Test Plan: Imported from OSS

Reviewed By: pbelevich

Differential Revision: D30523133

Pulled By: jamesr66a

fbshipit-source-id: b04cc0d842a74862f42ecba98b757310cd2ec7b0
2021-08-30 19:56:46 -07:00

22 lines
929 B
Python

from torch.fx.proxy import Proxy
from ._compatibility import compatibility
@compatibility(is_backward_compatible=False)
def annotate(val, type):
# val could be either a regular value (not tracing)
# or fx.Proxy (tracing)
if isinstance(val, Proxy):
if val.node.type:
raise RuntimeError(f"Tried to annotate a value that already had a type on it!"
f" Existing type is {val.node.type} "
f"and new type is {type}. "
f"This could happen if you tried to annotate a function parameter "
f"value (in which case you should use the type slot "
f"on the function signature) or you called "
f"annotate on the same value twice")
else:
val.node.type = type
return val
else:
return val