InStr function returns pseudo True/False?

**GCW esq** · 07-03-2012, 07:00 AM

I have been playing with the Instr function (Excel 2003), and it appears to behave as though it's returning a True/False value.
For example, the following will print "1":

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I said "pseudo" above because if the code tests for "True", it doesn't find it. The following prints "0":

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What's the go? Safe to use it like that (boolean)?

**Steffen Thomsen** · 07-03-2012, 07:05 AM

Hi,

Instr returns the position of the match

This means if instr returns 0 no match is found

If it returns > 0 then a match is found

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**JosephP** · 07-03-2012, 07:57 AM

your first example works because vba performs an implicit coercion to a boolean (0 = false, any other number = true). the second fails because your explicit comparison is false (True = -1, not the 2 your InStr returns). as steffen said it is much better to compare to 0.

**GCW esq** · 07-03-2012, 08:23 AM

So what's the value of making it explicit?
More obvious to others (and to me in a year's time) what's going on?
Less chance of making an error?
It seems pretty clear in an IF statement what's happening, n'est-ce pas?

**JosephP** · 07-03-2012, 08:34 AM

Originally Posted by GCW esq

So what's the value of making it explicit?
More obvious to others (and to me in a year's time) what's going on?
Less chance of making an error?

both. would you really use

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when coding?

It seems pretty clear in an IF statement what's happening, n'est-ce pas?

it seems not since you asked this question. ;-)
what benefit do you see in the former syntax given the confusion it has caused you? InStr does not return a boolean, it returns a long (well, variant) so why not use it that way?

**GCW esq** · 07-03-2012, 08:39 AM

Thanks, JosephP. I wasn't really confused. I just thought I was seeing a neater way to do things, and wondering why not?
(Said sadly) I guess you're right. I'll go back to my old, explicit ways. SIGH!

**JosephP** · 07-03-2012, 08:44 AM

I'm not saying you can't use it that way-you certainly can. I just don't think it's the best option partly because you'll probably try and use that = True comparison again at some point and it won't work but won't return an error either. of course, I can't think of any reason to use an '= True' comparison at all: if something is true, there ain't much point comparing it to True just to return True again. :-)

**GCW esq** · 07-04-2012, 08:00 AM

Yes, thanks.
The only reason I used the "=True" was to test what the code was doing. I didn't actually try to use it in anything, so no worries there.
I see your point though. Probably best to keep it explicit.