bash choping strings

#!/bin/bash
 
# http://www.ibm.com/developerworks/library/l-bash.html
# how to chopping strings?
 
# basename and dirname
path='/usr/local/share/doc/foo.txt'
 
basename $path   # foo.txt
echo ${path##*/} # foo.txt
 
dirname $path    # /usr/local/share/doc
echo ${path%/*}  # /usr/local/share/doc
 
# professional chopping
var="somestring"
 
echo ${var#*s}  # omestring
echo ${var##*s} # tring
 
echo ${var%s*}  # some
echo ${var%%s*} # null!
 
echo ${var%%ng*} # somestri
echo ${var%%ing} # somestr
 
echo ${var:0:4}  # some

var="somestring"
echo ${var/some/any} # anystring