Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> writes: > Em Thu, 03 Jul 2025 17:47:13 -0600 > Jonathan Corbet <corbet@xxxxxxx> escreveu: > >> Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> writes: >> >> > Em Thu, 3 Jul 2025 12:43:58 -0600 >> > Jonathan Corbet <corbet@xxxxxxx> escreveu: >> > >> >> Rework _add_regex() to avoid doing the lookup twice for the (hopefully >> >> common) cache-hit case. >> >> >> >> Signed-off-by: Jonathan Corbet <corbet@xxxxxxx> >> >> --- >> >> scripts/lib/kdoc/kdoc_re.py | 7 ++----- >> >> 1 file changed, 2 insertions(+), 5 deletions(-) >> >> >> >> diff --git a/scripts/lib/kdoc/kdoc_re.py b/scripts/lib/kdoc/kdoc_re.py >> >> index e81695b273bf..612223e1e723 100644 >> >> --- a/scripts/lib/kdoc/kdoc_re.py >> >> +++ b/scripts/lib/kdoc/kdoc_re.py >> >> @@ -29,12 +29,9 @@ class KernRe: >> >> """ >> >> Adds a new regex or re-use it from the cache. >> >> """ >> >> - >> >> - if string in re_cache: >> >> - self.regex = re_cache[string] >> >> - else: >> >> + self.regex = re_cache.get(string, None) >> > >> > With get, None is default... >> > >> >> + if not self.regex: >> >> self.regex = re.compile(string, flags=flags) >> > >> > ... yet, as you're using get, better to code it as: >> > >> > self.regex = re_cache.get(string, re.compile(string, flags=flags)) >> >> ...but that will recompile the regex each time, defeating the purpose of >> the cache, no? > > No. It should do exactly like the previous code: > > - if re_cache[string] exists, it returns it. > - Otherwise, it returns re.compile(string, flags=flags). > > https://www.w3schools.com/python/ref_dictionary_get.asp The re.compile() call is evaluated before the call to get() - just like it would be in C. This is easy enough to prove to yourself in the REPL if you doubt me... Thanks, jon
