Interesting, I've never noticed that. (I insist on the parentheses in
my code, so always use Call.)
You get a syntax error when you compile the two parameter Sub reference.
However, when you type it in (in 2003), you get "Expected: =". Looks as
though it's syntax-checking my "bb(1, 2)" as an index into an array bb,
even though there isn't one, and there's definitely a Sub bb.
Interestingly, this happens even if Sub bb appears in the code of the
module before the call to it.
I changed the statement to "bb(1, 2) = 1" and this generates an
"Expected Function or variable" error. So it could also be expecting bb
to be a Function, returning a Variant or Object, that would allow it to
be used on the left of the equals.
> Does anyone know why the single argument works
> with a parentheses?
Or the converse, why you can't do it for multiple arguments ...
Flaky syntax analysis, I suspect. I wonder if it's fixed in 2007 or
2010.
==================================================
Aha ... just found something in
http://stackoverflow.com/questions/479891/what-does-the-call-keyword-do-
in-vb6
Try the following code
Option Explicit
Sub tester()
Dim a As String: a = "Original"
Call Test(a)
Dim b As String: b = "Original"
Test b
Dim c As String: c = "Original"
Test (c)
Range("A1").Value = "a = " & a & ", b = " & b & ", c = " & c
End Sub
Sub Test(ByRef param As String)
param = "Test changed it"
End Sub
Result is: a = Test changed it, b = Test changed it, c = Original
so we have it.
The call with no Call and the single parameter in parentheses is
evaluating the (c) as a string expression. The call with a Call passes
a as a byref variable. The call with no Call and no parentheses b as a
byref variable.
So my "bb(1, 2)" fails because it attempts to evaluate "(1, 2)" as a
string expression, which is bad syntax. It possibly also attempts to
interpret "bb(1, 2)" as an array reference and also as a function call,
but it gives up and can't decide what the problem is ... hence "Syntax
error".
Regards, Dave S
________________________________
From: ExcelVBA@yahoogroups.com [mailto:ExcelVBA@yahoogroups.com] On
Behalf Of mickey11030
Sent: Friday, 14 December 2012 13:18
To: ExcelVBA@yahoogroups.com
Subject: [ExcelVBA] Using Parentheses in Subroutine Calls
The rule is that if you call a subroutine using the Call keyword, you
must enclose the argument list in parentheses. That is
Call Test(a, b)
is correct. But if you omit Call, you must not use parentheses, so that
Test a, b
is also correct. I didn't know these rules, and, from habit, I do not
use Call and do use parentheses. I got away with that for a long time
because my subroutines used only 1 argument. Surprisingly,
Test (c)
works even though it violates the rule. I got into trouble only when I
wrote a subroutine that used 2 arguments.
Test (c, d)
causes a syntax error. Does anyone know why the single argument works
with a parentheses?
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