pure-shell version of "perl -MDDP -e 'p %ENV'"

myenv.sh

#/usr/bin/env bash

names=();
values=();
biggest=0;

# first we separate ENV in keys and values,
# and fetch the size of the biggest key
for ITEM in `env`
do
  name=${ITEM%%=*};
  if [ ${#name} -gt $biggest ]
  then
    biggest=${#name};
  fi
  names[${#names[*]}]=$name
  values[${#values[*]}]=${ITEM#*=}
done

# now we print our output in a nicely formatted way :)
for (( i = 0; i < ${#names[*]}; i++ ))
do
  printf '\E[35;40m%-*s\E[0m    \E[33;40m"%s"\E[0m\n' $biggest ${names[$i]} ${values[$i]};
done

# ANSI screen colours cheat-sheet:
#
# \E[FORECOLOUR;BGCOLOURm Text goes here \E[0m
#
# * FORECOLOUR is the text colour
# * BGCOLOUR is the background colour
# * don't forget the tiny 'm' after the bgcolours
# * \E[0m resets the colours
#
# Note: fg and bg colour codes do not overlap, so the actual order doesn't matter.
#
# Colour    Foreground  Background
# black         30         40
# red           31         41
# green         32         42
# yellow        33         43
# blue          34         44
# magenta       35         45
# cyan          36         46
# white         37         47