Geoff Clare via austin-group-l at The Open Group wrote in <Z_6RJa7JNDJ-ESrp@localhost>: |Steffen Nurpmeso wrote, on 15 Apr 2025: |> Geoff Clare via austin-group-l at The Open Group wrote in |> <Z_5vwwvojBKpOJl7@localhost>: |>|Chet Ramey wrote, on 11 Apr 2025: |>|> The question is whether shells will agree on *which* empty fields are |>|> discarded. |>|[...] |>|> For everyone who isn't on the bash mailing list, this is the message |>|> from kre that Steffen is referring to that explains the bash and NetBSD |>|> sh behavior. |>|> |>|> https://lists.gnu.org/archive/html/bug-bash/2025-03/msg00030.html |>| |>|Okay, with Chet's clue and kre's detailed description, I now see that |>|my expectation of "empty fields may be discarded" leading to exactly |>|two conforming behaviours was wrong. I had naïvely assumed that each |>|shell would either discard all empty fields or retain all empty fields. |> |> Disclaimer: i will agree with your conclusion below. | |Perhaps you changed your mind by the time you finished the email, |because I don't see an agreement with my conclusion. | |> *But*. No, his description is not right. | |My take-away from his description was that shells can discard some |empty fields and retain others. I didn't actually look too closely |at his explanation of the expansion(s). | |Now that I've looked again, I can see that he made some major |mistakes. For example: | |kre> This output (from your message) shows what is happening | |kre> | 4,1=:a:/ a ,2=a/a,3=/,4=a | |kre> Showing that $1 is ":a:/ a " $2 is "a" $3 is "" and $4 is 'a' | |No, $1 is ":a:". The part after the / is from the unquoted expansion |of $1 (with spaces produced by echo). | |After that he says: | |kre> There is a space at the end of $1, so ... | |but there is no space at the end of $1, so any reasoning based on |that is bogus. | |> then he says |> |> The ':' really has little to do with it, the space is a data |> char, it isn't in IFS, so isn't going to be touched by field |> splitting | |Again, there is no space. | |Given these mistakes, I think we need kre (and Chet because he |believed kre's description) to revisit their positions on this.
With the stubborn obeisance and sympathy that Germans inflame for British positions over and over again. |-- |Geoff Clare <[email protected]> |The Open Group, Apex Plaza, Forbury Road, Reading, RG1 1AX, England --End of <Z_6RJa7JNDJ-ESrp@localhost> --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)
