= lists nil and null

From: Jeff Kish (ELN/kishj_at_earthlink.net)
Date: 11/27/03 

Date: Thu, 27 Nov 2003 13:40:58 -0600

Can someone tell me why (below) (= temp nil) and (=temp null) don't evaluate (blow up)?
I thought that you could compare null to a list to see if it was empty. Isn't (setq temp()) setting
temp to an empty list?

[12]> (setq temp ())
NIL
[13]> temp
NIL
[14]> (= temp nil)

*** - =: NIL is not a NUMBER
The following restarts are available:
USE-VALUE :R1 You may input a value to be used instead.

1. Break [15]> (= temp null)

*** - EVAL: variable NULL has no value
The following restarts are available:
STORE-VALUE :R1 You may input a new value for NULL.
USE-VALUE :R2 You may input a value to be used instead of NULL.
USE-VALUE :R3 You may input a value to be used instead.

2. Break [16]>

Thanks

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