Fabian Stelzer <fs@xxxxxxxxxxxx> writes: > On 15.11.2021 18:44, Ævar Arnfjörð Bjarmason wrote: >> >>On Mon, Nov 15 2021, Fabian Stelzer wrote: >> >>> +if test -n "$missing_prereq" >>> +then >>> + unique_missing_prereq=$( >>> + echo $missing_prereq | >>> + tr -s "," "\n" | >>> + grep -v '^$' | >>> + sort -u | >>> + paste -s -d ',') >> >>What is paste? Some out-of-tree debugging utility? >> >>I think you might find a better way to do this shown in my >>"ab/generate-command-list" topic, currently in seen. It removed most of >>the same sort of tr|grep|sort etc. chain in generate-cmdlist.sh. > > I've looked at the generate-command-list code and TBH i still think this > is a better solution. If I read your change correctly you've removed the > sort and unique completely since it was not necessary for the use-case. > In this case i think it is. Since we call tr with `-s` the grep -v might > not be strictly necessary though. Also in this case these commands are > only called once at the end of the test run and not in any kind of loop > like in the cmdlist code so i think this variant is much easier to read > and debug with a negligible performance impact. I tend to agree with you. The snippet we see above is quite straight-forward not over-engineered. > I tried writing a sh only variant and this is what i came up with. Not > sure if this could be much more simplified. It looses the sort though. Fun, but I'd rather not go there, unless this is a performance critical bit, which it is not. Thanks. > > input="PCRE,JGIT2,JGIT2,,PCRE,JGIT2,PCRE,PCRE2,!PCRE,!WINDOWS,GPG,GPGSSH,PCRE,!GPG,GPG,JGIT2" > > unique= > save_IFS=$IFS > IFS=, > for prereq in $input > do > case "$prereq" in > '') > # Skip empty entries > ;; > *) > case ",$unique," in > *,$prereq,*) > # Skip over duplicates > ;; > *) > if test -z "$unique" > then > unique="$prereq" > else > unique="$unique,$prereq" > fi > ;; > esac > esac > done > IFS=$save_IFS > echo $unique
