# Suppress leading repeated number string in two numbers that are separated
# by a double-dash.
# Usage:
#    sed -f bbl.sed < inp.bbl > out.bbl
# Examples:
# 834--837  in stdin is replaced by 834--7 on output. "83" is suppressed.
# 834--847  in stdin is replaced by 834--47 on output. "8" is suppressed
# 834-837  in stdin is not changed (because only a single dash is found) 
# 834--937  in stdin is not changed because there is no common starting string.
# 
# Richard J. Mathar, http://www.strw.leidenuniv.nl
# 2006-12-15
s/\([^0-9][-0-9]*\)\(.\)--\1\(.\)/\1\2--\3/g
s/\([^0-9][-0-9]*\)\(..\)--\1\(..\)/\1\2--\3/g
s/\([^0-9][-0-9]*\)\(...\)--\1\(...\)/\1\2--\3/g
s/\([^0-9][-0-9]*\)\(....\)--\1\(....\)/\1\2--\3/g
s/\([^0-9][-0-9]*\)\(.....\)--\1\(.....\)/\1\2--\3/g