Hi Sorin,

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Case 2.
sExp = NULL - is an expression only as "sExp = NULL" where the text string expresses that sExp = NULL, IOW the expression is that sExp is undefined. NULL is a value, not an expression.
Therefore, only EVALUATE("sExp = NULL") makes sense. EVALUATE(NULL) does not make sense => ERROR.
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This is a general
This is the interpretation made from the VFPT.

My interpretation is of general type:

In a language that supports the NULL,
whichever function with all the null parameters must give back:
- or a predefined value
- or NULL

Put NULL on a optional parameters or not put a value on it, is equal.

In fact

? DATE(null,null,null)
? TIME(null)
? DATETIME(null,null,null,null,null,null)

are correct.

Example:

* these simple VFP functions not support NULL
? ADDBS(null)
? QUARTER(null , null) && but WEEK(null,null,null) yes
? EVALUATE(null)
? ALIAS(null)
? SELECT(null)
? SYS(null)
? FKLABEL(null)
.....

For me, SQL Server support NULL.

On SQL Server exists a native function that not support all NULL parameters ?

Fabio