ohmyzsh/lib/rvm.zsh

# get the name of the ruby version
function rvm_prompt_info() {
  [ -f $HOME/.rvm/bin/rvm-prompt ] || return 1
  local rvm_prompt
  rvm_prompt=$(eval "$HOME/.rvm/bin/rvm-prompt $ZSH_THEME_RVM_PROMPT_OPTIONS" 2>/dev/null)
  [[ "${rvm_prompt}x" == "x" ]] && return 1
  echo "${ZSH_THEME_RVM_PROMPT_PREFIX:=(}${rvm_prompt}${ZSH_THEME_RVM_PROMPT_SUFFIX:=)}"
}