Chet Ramey schrieb:
Bernd Eggink wrote:
Chet Ramey schrieb:
Hm, compgen appears to behave strange if words contain whitespace.
Well, it splits the argument to -W on $IFS as documented. What other
strange behavior do you see?
For example, this:
function _aha
{
local list="a b:c d:e f"
COMPREPLY=($(IFS=: compgen -W "$list"))
}
complete -F _aha aha
Typing aha <Tab> cycles through 6 items a, b, c, d, e, f, whereas I
would expect 3 items 'a b', 'c d', 'e f'. It looks like compgen splits
the argument to -W on $IFS _and_ whitespace. Or am I missing something?
I don't think you're considering the interaction between compgen,
command substitution, and compound array assignment.
I'll use the assignment to `list' you used above for the explanation.
compgen performs word splitting using $IFS and then outputs the results,
one word per line:
$ IFS=: compgen -W "$list"
a b
c d
e f
Command substitution takes that, chops off the last newline, and, since
it's unquoted, performs word splitting using $IFS on the result:
$ recho $(IFS=: compgen -W "$list")
argv[1] = <a>
argv[2] = <b>
argv[3] = <c>
argv[4] = <d>
argv[5] = <e>
argv[6] = <f>
If you want to preserve the embedded newlines, you have to quote the
expansion (but see below):
$ recho "$(IFS=: compgen -W "$list")"
argv[1] = <a b^Jc d^Je f>
When performing compound array assignments, though, the words between
the parens undergo all the shell word expansions, including word splitting:
$ COMPREPLY=( $(IFS=: compgen -W "$list") )
$ recho "${comprep...@]}"
argv[1] = <a>
argv[2] = <b>
argv[3] = <c>
argv[4] = <d>
argv[5] = <e>
argv[6] = <f>
So you can split on just the embedded newlines by setting $IFS:
$ oifs="$IFS"
$ IFS=$'\n' COMPREPLY=( $(IFS=: compgen -W "$list") )
$ IFS="$oifs"
$ recho "${comprep...@]}"
argv[1] = <a b>
argv[2] = <c d>
argv[3] = <e f>
Remember to save and restore $IFS, though, since the assignment to it
preceding the assignment to COMPREPLY will persist.
Chet,
thanks for the clarification. It's actually quite obvious and I should
have seen it myself.
Regards,
Bernd
