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| author | Raymond Hettinger <rhettinger@users.noreply.github.com> | 2022-11-01 04:44:40 (GMT) |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2022-11-01 04:44:40 (GMT) |
| commit | f5afb7f2331efa8f64080576a75517c3a96442b9 (patch) | |
| tree | 8716a7a22dfe8c1d8bf94855f8fc9ba073a1730e /Lib/collections | |
| parent | 5cf317ade1e1b26ee02621ed84d29a73181631dc (diff) | |
| download | cpython-f5afb7f2331efa8f64080576a75517c3a96442b9.zip cpython-f5afb7f2331efa8f64080576a75517c3a96442b9.tar.gz cpython-f5afb7f2331efa8f64080576a75517c3a96442b9.tar.bz2 | |
GH-98766: Modest speed-up from ChainMap.__iter__ (GH-98946)
Diffstat (limited to 'Lib/collections')
| -rw-r--r-- | Lib/collections/__init__.py | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/Lib/collections/__init__.py b/Lib/collections/__init__.py index 5860787..f07ee14 100644 --- a/Lib/collections/__init__.py +++ b/Lib/collections/__init__.py @@ -1011,8 +1011,8 @@ class ChainMap(_collections_abc.MutableMapping): def __iter__(self): d = {} - for mapping in reversed(self.maps): - d.update(dict.fromkeys(mapping)) # reuses stored hash values if possible + for mapping in map(dict.fromkeys, reversed(self.maps)): + d |= mapping # reuses stored hash values if possible return iter(d) def __contains__(self, key): |