需求：
将1 and 2 and 3变成2 and 4 and 6 (倍数关系)
方法：
Python
def computereplacement(matchobj):
return str(int(matchobj.group()) * 2)
import re
subject = '1 and 2 and 3'
regobj = re.compile(r"\d+")
result = regobj.sub(computereplacement,subject)
print result
Tcl:
set pos 0 set subject "1 and 2 and 3" while {[regexp -indices -start $pos -linestop {\d+} $subject offsets]==1} { set pos [expr {1+[lindex $offsets 1]}] set start [lindex $offsets 0] set end [lindex $offsets 1] set element [string range $subject [lindex $offsets 0] [lindex $offsets 1]] set subject [string replace $subject $start $end [expr $element * 2]] } puts "subject:$subject"
