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In Python 3.11+ it's better to do `tuple([])`, for older Python it
doesn't matter much.
The reason is that `tuple(x for x in xs)` creates a generator function
where cpython goes between to frames, whereas `tuple([x for x in xs])`
is native iteration.
Further, remove the indirection of the `HashableMap.__iter__` function
call, and do not use splatting in `StandardVersion.from_string`.
Before:
```
$ python -m timeit -s 'from spack.spec import Spec; s = Spec("[email protected] foo=bar")' 'hash(s)'
100000 loops, best of 5: 2.66 usec per loop
$ python -m timeit -s 'from spack.version import ver' 'ver("1.2.3")'
200000 loops, best of 5: 1.82 usec per loop
```
After:
```
$ python -m timeit -s 'from spack.spec import Spec; s = Spec("[email protected] foo=bar")' 'hash(s)'
200000 loops, best of 5: 1.58 usec per loop
$ python -m timeit -s 'from spack.version import ver' 'ver("1.2.3")'
200000 loops, best of 5: 1.54 usec per loop
```
Signed-off-by: Harmen Stoppels <[email protected]>
haampie
changed the title
alalazo
approved these changes
Jan 14, 2026
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Extracted from #51836
In Python 3.11+ it's better to do
tuple([...])instead oftuple(...). Forolder Python it doesn't matter much.
The reason is that
tuple(x for x in xs)creates a generator functionwhere cpythonn needs another stack frame, whereas
tuple([x for x in xs])is native iteration equivalent to
lst = []; for x in xs: lst.append(x); tuple(lst),except that
appendis not a function call but an intrinsic.Further, remove the indirection of the
HashableMap.__iter__functioncall, and do not use splatting in
StandardVersion.from_string.Before:
After:
On my macbook it gives small (4.8%) reduction in package load time.