TextMate environment variable reference

textmate_environment_variables.rb

#!/usr/bin/env ruby

###############################################################
#
#   Paste this into a TextMate document, 
#   press ⇧^⌥R and choose 'Ruby' from the menu that appears,
#   and then press ⌘R to run this in the context of TextMate
#   to see all TextMate environment variables and their values
#
###############################################################



def display(environment_variable)
  puts "### #{environment_variable} ###"
  puts ENV[environment_variable]
  puts 
end

display 'TM_APP_IDENTIFIER'
display 'TM_APP_PATH'
display 'TM_BUNDLE_ITEM_NAME'
display 'TM_BUNDLE_ITEM_UUID'
display 'TM_BUNDLE_SUPPORT'
display 'TM_COLUMN_NUMBER'
display 'TM_COMMENT_START'
display 'TM_COMMENT_START_2'
display 'TM_COMMENT_END_2'
display 'TM_CURRENT_LINE'
display 'TM_CURRENT_THEME_PATH'
display 'TM_DISPLAYNAME'
display 'TM_DOCUMENT_UUID'
display 'TM_FULLNAME'
display 'TM_GIT'
display 'TM_LINE_INDEX'
display 'TM_LINE_NUMBER'
display 'TM_LINK_FORMAT'
display 'TM_MATE'
display 'TM_PID'
display 'TM_QUERY'
display 'TM_RUBY'
display 'TM_SCM_COMMIT_WINDOW'
display 'TM_SCOPE'
display 'TM_SCOPE_LEFT'
display 'TM_SELECTION'
display 'TM_SOFT_TABS'
display 'TM_SUPPORT_PATH'
display 'TM_TAB_SIZE'
display 'TM_THEME_PATH'

TM_HG
TM_FILEPATH
DIALOG1
DIALOG1_PORT_NAME
DIALOG_PORT_NAME
MATEFLAGS
TM_ERROR_FD
TM_FILENAME
TM_FILE_IS_UNTITLED
TM_ORGANISATION
TM_PROPERTIES_PATH

There's now a better way to do this, though I have no idea when it was added. Use command-control-/ to open a list of all set TextMate variables.