Re: Value vs. Const

[Joel Cochran <jrc@xxxxxxxxxx>]

Just to clarify so others can learn from my mistake:

I *was* checking for whether or not the parm was passed using %parms(). 
My mistake came when the parm was not sent: I would then populate the
parm with a default value and use the parm as a local variable.  This is
the no-no I was referring to before.

Now by using const instead of value, I still use %parms() to check and
see if the parm was passed, but now I have a local variable with my
default value and I only change it if the parm was sent.  Now in my
program I'm using the lcoal variable instead and all is well.

The only reason that I specify const instead of value is simply as a
convention: now I cannot change the value of the parm to a default if
not sent: if I want this behavior I'm forced to use a true local
variable instead.

Clear as mud? :-)

Joel

On Thu, 2003-08-07 at 18:54, Scott Klement wrote:
> > One caveat that Barbara Morris pointed out to me is that using "value"
> > and "options(*nopass)" on the same variable can be dangerous.  If you
> > want a variable to be *nopass and still take advantage of the VALUE
> > benefits, then use CONST...
> 
> Joel... there's nothing special about VALUE in this circumstance.   You
> should never reference ANY parameter that has not been passed.   It does
> not matter whether it's passed by VALUE or REFERENCE or CONST... you
> should *always* check with %parms to before using an "optional" variable.
> 
> 
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