Date:         Fri, 28 Apr 2000 00:13:13 -0400
Reply-To:     Tom Frenkel <taf2@IS8.NYU.EDU>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Tom Frenkel <taf2@IS8.NYU.EDU>
Subject:      Re: length of variable assigned to substr function.
Comments: To: paula <icj808@USWEST.NET>
In-Reply-To:  <e16O4.852$XB6.40969@news.uswest.net>
Content-Type: TEXT/PLAIN; charset=US-ASCII

Paula --

The rules for how the length of a character variable is decided seem
complicated to me.  So to be safe, I *always* declare its length --
*before* its first use! -- with a LENGTH statement. I don't see how this
could ever do any harm.  And the little bit of extra typing seems a small
price to pay for the peace of mind thus gained.

        --Tom
        Tom Frenkel <taf2@is8.nyu.edu>
        http://pages.nyu.edu/~taf2

> There is this rountine assignment
>
> xyz = substr (uvwxyz, 1, 1);
> zyx = substr (uvwxyz, 2, 1);
> yxz =substr (uvwxyz, 3,1);

> The original variable uvwxyz is of $6. Now it is so said (not by the
> reference manual) that the length of the three new variables to the
> left of the assignment are all determined by that of the original
> UVWxyz.

> So should I use a Length statement to declare the length for them
> first? Is this generalizable to many other functions? such as
> Compress, or just a rule specific to this substr for a good reason?