From: Daniel Schoch [mailto:trash / tekwissusa.com] 
# Dominik Honnef wrote:
# > | >>> DIR=x FILE=y.z irb
# > | >> s = "$DIR/test/$FILE".gsub(/\$\w+/) {|m| ENV[m[1..-1]]}
# > | => "x/test/y.z"
# Perfect, thanks. I sometimes have a hard time with those 
# efficient one-liners. It's all so cryptic.


if we are careful w constants (wc we should), we can do,

  s = "DIR/test/FILE".gsub(/[A-Z]+/) {|m| ENV[m]}

(ok, ok, you guessed it, i hate dollar notations =)

kind regards -botp