Re: Arrays

[Steffen Nurpmeso <steffen@xxxxxxxxxx>]

Steven Penny wrote in <5ceae7fb.1c69fb81.e00c9.71f8@xxxxxxxxxxxxx>:
 |The Bash shell makes it possible to create arrays:
 |
 |https://gnu.org/software/bash/manual/html_node/Arrays
 |
 |Dash shell currently does not have this feature. A workaround is to \
 |use ARGV:
 |
 |    $ set aaa bbb ccc
 |    $ echo "$2"
 |    bbb
 |
 |However this is limited as only one array can exist at a time, while \
 |Bash allows
 |multiple arrays to exist at a time:
 |
 |    $ gg=(aaa bbb ccc)
 |    $ hh=(ddd eee fff)
 |    $ echo "${gg[1]} ${hh[1]}"
 |    bbb eee

kre happily shared his code to quote from and to variables:

  #@ Round trip quote strings in POSIX shell.  E.g.,
  #@  set -- x 'a \ b' "foo'" "\\'b\\a\\r\\" Aä
  #@  printf "%s: <%s><%s><%s><%s><%s>\n" "$#" "${1}" "${2}" "${3}" "$4" "$5"
  #@  saved_parameters=`quote_rndtrip "$@"`
  #@  eval "set -- $saved_parameters"
  #@  printf "%s: <%s><%s><%s><%s><%s>\n" "$#" "${1}" "${2}" "${3}" "$4" "$5"
  
  # Though slower use a subshell version instead of properly restoring $IFS
  # and flags, as elder shells may not be able to properly restore flags via
  # "set +o" as standardized in POSIX, and it seems overkill to handle all
  # possible forms of output that "set +o" may or may not actually generate
  quote__rndtrip() (
     case "$1" in
     *\'*) ;;
     *) printf "'%s'" "$1"; return 0;;
     esac
     __A__="$1" __S__= __E__=
     while case "$__A__" in
        \'*)  __A__=${__A__#?}; __S__="${__S__}\\\\'";;
        *\')  __A__=${__A__%?}; __E__="${__E__}\\\\'";;
        '')   printf "${__S__}${__E__}"; exit 0;;
        *) false;;
        esac
     do
        continue
     done
     IFS=\'
     set -f
     set -- $__A__
     _result_="${1}"
          shift
     for __A__
     do
        _result_="${_result_}'\\''${__A__}"
     done
     printf "${__S__}'%s'${__E__}" "${_result_}"
     exit 0
  )
  
  quote_rndtrip() {
     j=
     for i
     do
        [ -n "$j" ] && printf ' '
        j=' '
        quote__rndtrip "$i"
     done
  }
  
  quote_string() {
     j=
     for i
     do
        [ -n "$j" ] && printf '\\ '
        j=' '
        quote__rndtrip "$i"
     done
  }

--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)