Can not figure out, how to get the bash-completion work with arguments containing "::" like that, because compgen or complete take each entry as seperate word, I guess.
cmd=./my_script
_my_options()
{
  local cur prev opts
  cur=${COMP_WORDS[COMP_CWORD]}
  prev=${COMP_WORDS[COMP_CWORD-1]}
  opts="NAMESPACE::param1 NAMESPACE::param2 NAMESPACE::param3 NAMESPACE2::param1 NAMESPACE2::param2"
  COMPREPLY=( $(compgen -W '$opts' -- $cur ) );
}
complete -F _my_options $cmd
Bash-Completion stops working here..
$ ./my_script <TAB>
$ ./my_script NAMESPACE
NAMESPACE2::param1  NAMESPACE::param1   NAMESPACE::param3
NAMESPACE2::param2  NAMESPACE::param2   
1. $ ./my_script NAMESPACE    <TAB> or <TAB><TAB> -> no effect
2. $ ./my_script NAMESPACE:   <TAB> or <TAB><TAB> -> no effect
3. $ ./my_script NAMESPACE::  <TAB> or <TAB><TAB> -> no effect
4. $ ./my_script NAMESPACE::p <TAB> or <TAB><TAB> -> no effect
COMP_WORDS are NAMESPACE, :: and param1 instead of only one string  NAMESPACE::param1.
With quotes the autocomplete works, but I do not want to pass those quotes.
5. $ ./my_script "<TAB>
   $ ./my_script "NAMESPACE
   $ ./my_script "NAMESPACE:<TAB>
   $ ./my_script "NAMESPACE::param
   $ ./my_script "NAMESPACE::param1"