ex16.tcl

很不错的tcl编程实例

# Copyright 1996


# Authors

# Lakshmi Sastry
# Computing and Information Systems Department
# Rutherford Appleton Laboratory, Chilton, Didcot. OX11 0QX
# [e-mail]

#                         and

# Venkat VSS Sastry
# Department of Applied Mathematics and Operational Research
# Cranfield University, RMCS Shrivenham, Swindon, SN6 8LA
# [e-mail]

# Permission to use, copy, modify, and distribute this
# software and its documentation for any purpose and without
# fee is hereby granted, provided that this copyright
# notice appears in all copies.
  
# The authors, RAL, RMCS Shrivenham and Cranfield University
# make no representations about the suitability of this
# software for any purpose.  It is provided "as is" without
# express or implied warranty. Likewise they accept no responsibility
# whatsoever for any public domain software modules used (which are
# hereby acknowledged) in this software 


# upvar_ex1.tcl
#
# upvar provides a general mechanism to access variables that
#    are outside the scope of the current procedure. It also is possible to
#    access variables from any level in the call stack, including the 
#    global level
# 
set months {January February March April May June July August \
		  September October November December}
#
proc thisMonth {} {
    ;# access the the variable months in the global scope
	 upvar #0 months x
	 puts stdout "Last month is : [lindex $x 11]"
    puts stdout "First month is : [lindex $x 0]"
}
#
# invoke thisMonth
#
thisMonth