How do I check to see if an environment variable exists?

[Stephen MacLean]

Thanks all!

I am basically doing what Jacqueline does and check to see if empty and then verify against a list of switches.

It does seem strange that we can’t check for the existence of a variable, but this works.

Thanks,

Steve MacLean

> On Nov 24, 2018, at 11:35 AM, J. Landman Gay via use-livecode <use-livecode at lists.runrev.com> wrote:
> 
>> How would I test to see if the $1 variable exists?
> 
> I don't check for existence, I only check whether it's empty.
> --
> Jacqueline Landman Gay | jacque at hyperactivesw.com
> HyperActive Software | http://www.hyperactivesw.com
> On November 24, 2018 8:04:50 AM bob--- via use-livecode <use-livecode at lists.runrev.com> wrote:
> 
>> $# tells you how many parameters there are for a script. Perhaps if $# > 0 then... instead might work (I’ve not tried that). You might find using environment() potentially helps as well. The Dictionary has the details. If neither of those options work let me know. I have another way you could tackle the issue.
>> 
>> - Bob Hall
>> 
>>> On Nov 23, 2018, at 5:27 PM, Stephen MacLean via use-livecode <use-livecode at lists.runrev.com> wrote:
>>> 
>>> However, the exists($1) never returns true, even when it should. Which leads to to believe that’s not what I want to use.
>>> 
>>> How would I test to see if the $1 variable exists?
>> 
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