saveval

来自「Calc Software Package for Number Calc」· 代码 · 共 75 行

NAME
    saveval - enable or disable saving of values

SYNOPSIS
    saveval(arg)

TYPES
    arg		any

    return	null value

DESCRIPTION
    When evaluation of a line of statements at top level starts, a
    "saved value" for that line is assigned the null value.  When saving
    is enabled (the initial state) and a statement being evaluated is an
    expression or a return statement, the value returned by that expression
    or statement replaces the current saved value; on completion of
    evaluation of the line, the saved value, if it is not null, updates
    the "oldvalue".

    This saving of values is enabled or disabled by calling saveval(arg)
    with an argument arg that tests as nonzero or zero,

    Whether saving is enabled or disabled does not affect the operation of
    eval(str).

EXAMPLE
    ; saveval(1);
    ; a = 27;
    .
	    27
    ; saveval(0);
    ; a = 45
    .
	    27
    ; saveval(1);
    ; a = 63
    .
	    63

LIMITS
    none

LINK LIBRARY
    none

SEE ALSO
    oldvalue, eval

## Copyright (C) 1999  Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
## as published by the Free Software Foundation.
##
## Calc is distributed in the hope that it will be useful, but WITHOUT
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
## or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU Lesser General
## Public License for more details.
##
## A copy of version 2.1 of the GNU Lesser General Public License is
## distributed with calc under the filename COPYING-LGPL.  You should have
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
##
## @(#) $Revision: 29.3 $
## @(#) $Id: saveval,v 29.3 2006/05/07 07:25:46 chongo Exp $
## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/saveval,v $
##
## Under source code control:	1997/09/06 20:03:35
## File existed as early as:	1997
##
## chongo <was here> /\oo/\	http://www.isthe.com/chongo/
## Share and enjoy!  :-)	http://www.isthe.com/chongo/tech/comp/calc/