pgj commented on code in PR #4659: URL: https://github.com/apache/couchdb/pull/4659#discussion_r1276109443
########## src/couch/src/couch_lists.erl: ########## @@ -0,0 +1,46 @@ +% Licensed under the Apache License, Version 2.0 (the "License"); you may not +% use this file except in compliance with the License. You may obtain a copy of +% the License at +% +% http://www.apache.org/licenses/LICENSE-2.0 +% +% Unless required by applicable law or agreed to in writing, software +% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT +% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the +% License for the specific language governing permissions and limitations under +% the License. + +-module(couch_lists). + +-export([uniq/1]). + +%% uniq/1: return a new list with the unique elements of the given list + +-spec uniq(List1) -> List2 when + List1 :: [T], + List2 :: [T], + T :: term(). + +-ifdef(OTP_RELEASE). +-if((?OTP_RELEASE) >= 25). +-define(HAS_LISTS_UNIQ, true). Review Comment: These are two nested `if`s where each could have its own `else` branches. This creates 3 possible branches: 1 for using `lists:uniq/1` directly and 2 for using its imported definition (no `OTP_RELEASE` defined or it is defined but its value is lesser than `25`). I wanted to avoid the code duplication for these latter ones. I know `HAS_LISTS_UNIQ` may look `autoconf`ish but it works nicely. For what it is worth, I was inspired by [`mochiweb`](https://github.com/mochi/mochiweb/blob/073349423408e4bae08c90f8d16fee5317e45263/examples/example_project/src/example_project_web.erl#L22-L32). -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
