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Re: brain twister



Paul van Delst <pvandelst@ncep.noaa.gov> wrote:

>> Okay, enough ideology for one week.
>
>That's *almost* a pun. :o)

Wow, I missed that one. Getting slow, I guess.

>> ----- Example 2
>> .comp
>> function test2, x
>>   return, x
>> end
>> 
>> a = dindgen(5)
>> (test2(a))[2] = -2
>> print, a
>
>You're right...this is weird. If you do a help:
>
>IDL> help, test2(a)
>A               DOUBLE    = Array[5]
>
>How come the result isn't
>
><Expression>    DOUBLE    = Array[5]

I wouldn't expect the result to be <Expression> becaues the result _is_ A,
so I would expect IDL to tell me that the result is A. We pass in a by
reference, return it, and so we should expect to get it back. I'm happy
that IDL can keep track of the variable through all that mucking around...
it makes sense to me.

Todd