# -*- mode: sh; sh-basic-offset: 3; indent-tabs-mode: nil; -*-
# vim: set filetype=sh sw=3 sts=3 expandtab autoindent:

# Append $2, $3, etc. to the array variable pointed to by $1.
# For example:
#   $ foo=(a)
#   $ append foo b c
#   $ echo "${foo[@]}"
#   a b c
# It can be used to concatenate arrays too:
#   $ append foo "${foo[@]}"
#   $ echo "${foo[@]}"  
#   a b c a b c
function append {
   # Get the variable name, so $@ only contains the elements to append
   varname="$1"
   shift
   # Here we quote the entire string passed to eval to prevent the
   # normal braces from creating parse errors. We also escape the $ in
   # the value, to ensure no stuff like pathname expansion is
   # performed on it (since $@ could contain anything). We can safely
   # expand $varname before evaluation, since we can be pretty sure that a
   # valid variable name does not contain any weird stuff like backticks
   # or tildes.
   # We need this eval in the first place to do indirect assignment and
   # indirectly reference the old value. The former could be done using
   # some export hack, which is perhaps a bit more elegant, but the
   # latter is not possible without eval it seems (there is the ${!var}
   # syntax, but stupid bash has assigned a different meaning to
   # ${!var[@]}, so you can't indirectly reference an array...
   eval "$varname=(\"\${$varname[@]}\" \"\$@\")"
}

# Does $1 occur in $2, $3, etc.?
function in_array {
   search=$1
   shift
   for i in "$@"; do
      if [ x"$i" == x"$search" ]; then
            # Found
            return 0
      fi
   done
   # Not found
   return 1
}