localenv - print only the variables defined in your current shell

localenv.sh

# All my gist code is licensed under the terms of the MIT license.

# put this in your .bashrc or something like that

# localenv
# print only the environment variables that were added 
# since the shell was started
function localenv () { 
  # this is done by comparing the output of 'set' in the current 
  # shell with the output of 'set' in a new shell.
  # A custom sed command excludes the variables that are always
  # different between shells (like PPID, SHELLOPTS, etc.), including
  # the ones defined in this function.
  local localenv_exclude=('BASH_EXECUTION_STRING' 'BASHOPTS' 'HISTFILESIZE'
  'HISTSIZE' 'PIPESTATUS' 'PPID' 'SHELLOPTS' 'SHLVL' '^_' 'BASH_ARGC' 'BASH'
  'ARGV' 'BASH_LINENO' 'BASH_SOURCE' 'FUNCNAME' 'localenv_exclude' 'localenv_exclude_sed');

  # prepend '^' and append '=' to each element, join with '|',
  # wrap in '/' and '/d'
  localenv_exclude=("${localenv_exclude[@]/#/^}");
  localenv_exclude=("${localenv_exclude[@]/%/=}");
  local localenv_exclude_sed=$(IFS="|"; echo "${localenv_exclude[*]}");
  localenv_exclude_sed="/$localenv_exclude_sed/d";

  command diff <(set | sed -E "$localenv_exclude_sed") \
    <(bash -i -c set | sed -E "$localenv_exclude_sed") | \
    sed -nE 's/^< (.*)/\1/p';
}