envchain completion (わからん)

.bash_profile

function _delegate() {
  local cur subs
  cur="${COMP_WORDS[COMP_CWORD]}" # partial word, if any
  subs=$(envchain -l)
  # echo "cword: $COMP_CWORD"
  # echo "cw: ${COMP_WORDS[COMP_CWORD]}"
  # echo "cl: ${COMP_LINE}, ccw: ${COMP_CWORD}, cp: ${COMP_POINT}, cw3: ${COMP_WORDS[2]}"

  if [[ $COMP_CWORD == 1 ]]; then
    # complete with the list of subcommands 
    COMPREPLY=( $(compgen -W "${subs}" -- ${cur}) )
  elif [[ $COMP_CWORD == 2 ]]; then
    # Two whole words before the cursor - delegate to the second arg
    # echo "Delegate $1, $2"
    # _command $2
    # complete -F _executables $1

    local exclude=$(compgen -abkA function | sort)
    local executables=$(compgen -c <(echo $exclude))
    #local executables=$(
    #    comm -23 <(compgen -c) <(echo $exclude)
    #    type -tP $( comm -12 <(compgen -c) <(echo $exclude) )
    #    type -tP $( comm -12 <(compgen -c) <(echo $exclude) )    #)
    COMPREPLY=( $(compgen -W "$executables" -- ${COMP_WORDS[COMP_CWORD]}) )

  elif [[ $COMP_CWORD -ge 3 ]] && [[ "${COMP_WORDS[2]}" == "aws" ]]; then
    aws_pos=$(($(echo "$COMP_LINE" | ggrep -abo " aws " | cut -d: -f1) + 1))
    # echo "pos $aws_pos"
    COMP_POINT=$((${COMP_POINT} - ${aws_pos}))
    # echo "${COMP_LINE:aws_pos}"

    # for bash:
    # COMP_LINE="${COMP_LINE:aws_pos}"

    # for zsh:
    COMP_LINE="${COMP_LINE:$aws_pos}"

    # echo "cl: ${COMP_LINE}, ccw: ${COMP_CWORD}, cp: ${COMP_POINT}"
    # COMP_LINE=(${COMP_LINE:2})
    # COMP_CWORD=$((${COMP_CWORD} - 2))
    # COMP_POINT=$((${COMP_POINT} - 10))
    COMPREPLY=($(COMP_POINT=$COMP_POINT COMP_LINE=$COMP_LINE aws_completer))
    # COMPREPLY=( $(compgen -Cc $3 -- ${COMP_WORDS[COMP_CWORD]}) )
  else
    COMPREPLY=()
  fi
}

complete -C aws_completer aws
complete -F _delegate envchain

function _executables {
    local exclude=$(compgen -abkA function | sort)
    local executables=$(
        comm -23 <(compgen -c) <(echo $exclude)
        type -tP $( comm -12 <(compgen -c) <(echo $exclude) )
    )
    COMPREPLY=( $(compgen -W "$executables" -- ${COMP_WORDS[COMP_CWORD]}) )
}