hadley/lubridate — pull request #165 by richierocks (2013-02-09 11:50:57+00:00)
Title: New function for retrieving Olson-style time zone names

Olson-style names are the most readable way of specifying time zones, but the only way to find out what values you can use is to dig around inside the R install directory (or hunt on Wikipedia).

I've added the function `olson_time_zones` that parses the file that ships with R, and returns the names in alphabetical order, or from West to East. Usage is

olson_time_zones()
#[1] "Africa/Abidjan" "Africa/Accra" "Africa/Addis_Ababa"
#[4] "Africa/Algiers" "Africa/Asmara" "Africa/Bamako"
#etc

olson_time_zones("longitude")
#[1] "Pacific/Midway" "America/Adak" "Pacific/Chatham"
#[4] "Pacific/Wallis" "Pacific/Tongatapu" "Pacific/Enderbury"
#etc