pick from whitelist of random themes for oh-my-zsh

gistfile1.sh

#Add to your .zshrc right by ZSH_THEME
#######

# Setup a random theme to load from a list I define
MYZSH_RANDOM_THEMES=(\
    're5et' \
    'sorin' \
    'steeef' \
    'dstufft' \
    'random' \
)

MYZSH_THEME_INDEX=${#MYZSH_RANDOM_THEMES[@]}
((MYZSH_THEME_INDEX=(RANDOM%MYZSH_THEME_INDEX)+1))

# Set name of the theme to load.
# Look in ~/.oh-my-zsh/themes/
# Optionally, if you set this to "random", it'll load a random theme each
# time that oh-my-zsh is loaded.
ZSH_THEME=${MYZSH_RANDOM_THEMES[${MYZSH_THEME_INDEX}]}