function zsh_stats() {
  fc -l 1 | awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | grep -v "./" | column -c3 -s " " -t | sort -nr | nl |  head -n20
}

function uninstall_oh_my_zsh() {
  env ZSH=$ZSH /bin/sh $ZSH/tools/uninstall.sh
}

function upgrade_oh_my_zsh() {
  env ZSH=$ZSH /bin/sh $ZSH/tools/upgrade.sh
}

function take() {
  mkdir -p $1
  cd $1
}

function open_command() {
  local open_cmd

  # define the open command
  case "$OSTYPE" in
    darwin*)  open_cmd="open" ;;
    cygwin*)  open_cmd="cygstart" ;;
    linux*)   open_cmd="xdg-open" ;;
    *)        echo "Platform $OSTYPE not supported"
              return 1
              ;;
  esac

  nohup $open_cmd "$@" &>/dev/null
}

#
# Get the value of an alias.
#
# Arguments:
#    1. alias - The alias to get its value from
# STDOUT:
#    The value of alias $1 (if it has one).
# Return value:
#    0 if the alias was found,
#    1 if it does not exist
#
function alias_value() {
    alias "$1" | sed "s/^$1='\(.*\)'$/\1/"
    test $(alias "$1")
}

#
# Try to get the value of an alias,
# otherwise return the input.
#
# Arguments:
#    1. alias - The alias to get its value from
# STDOUT:
#    The value of alias $1, or $1 if there is no alias $1.
# Return value:
#    Always 0
#
function try_alias_value() {
    alias_value "$1" || echo "$1"
}

#
# Set variable "$1" to default value "$2" if "$1" is not yet defined.
#
# Arguments:
#    1. name - The variable to set
#    2. val  - The default value 
# Return value:
#    0 if the variable exists, 3 if it was set
#
function default() {
    test `typeset +m "$1"` && return 0
    typeset -g "$1"="$2"   && return 3
}

#
# Set enviroment variable "$1" to default value "$2" if "$1" is not yet defined.
#
# Arguments:
#    1. name - The env variable to set
#    2. val  - The default value 
# Return value:
#    0 if the env variable exists, 3 if it was set
#
function env_default() {
    env | grep -q "^$1=" && return 0 
    export "$1=$2"       && return 3
}