Doh! I got so caught up in the range “thing” that I completely forgot about single non-range numbers. And yes, the leading number test should be for non-zero numbers, but in order to protect against someone entering 04-09 as a range, I made the Like test for leading numbers against Val(sInput) rather than against sInput directly (letting VB handle the behind-the-scenes conversion of the resulting number back to a String value). I also added an Else statement in my If..Then block to handle the stripping away of leading zeroes for single pages that might start with zero. And now, the final(?) code[grin]…

Nope, just simple inattention on my part.

>> or the 4 patters “-”, “,”, “,*” and “*,” (shouldn’t there be 6 patterns
>> including “*-” and “-*”?) rather than the 2 patterns “#*” and “*#”?

Same excuse, although you missed a simplification yourself… only one pattern test is needed… “#*#”

>> Fair point about spaces between numerals. They should be errors. But that makes the validation rules just
>> – no spaces between numerals, and after this check all spaces may be removed at which point
>> – no chars other than numerals, commas and hyphens
>> – no chars other than numerals in first and last positions
>> – no sequences of 2 or more non-numerals
>> – no more than 1 hyphen between commas

Charting it like this before starting to write any code (instead of writing code as I thought of each condition) is definitely the much, much better way to approach this problem… the code to handle the conditions when laid out like this is much easier to see. Because you can’t make Like searches “ungreedy”, the last item in the list has to be handled the way I currently do it… inside the loop after sInput is Split apart. Before finishing up, I just wanted to thank you for slapping-me-upside-of-my-head with all this, it was much appreciated. Okay, so here is the modified (and I think final[grin]) code for my approach to the original problem…

Fair point about spaces between numerals. They should be errors. But that makes the validation rules just
- no spaces between numerals, and after this check all spaces may be removed at which point
- no chars other than numerals, commas and hyphens
- no chars other than numerals in first and last positions
- no sequences of 2 or more non-numerals
- no more than 1 hyphen between commas

Okay, I corrected the leading trailing problem that you pointed out and I also modified the code to allow blank spaces everywhere except between digits and I also modified the code to allow hyphenated ranges in reverse order (the reverse ordering is preserved when the values are assigned into the returned array from the function)…

Function PagesToPrint(sInput As String) As Variant
Dim X As Long, Z As Long, Temp As String, sNumbers() As String, sRange() As String
If sInput Like “*# #*” Then GoTo Bad
sInput = Replace(sInput, ” “, “”)
If sInput Like “*[!0-9,-]*” Or sInput Like “*,-*” Or sInput Like “*-,*” Or _
sInput Like “*,,*” Or sInput Like “*–*” Or sInput Like “-” Or _
sInput Like “,” Or sInput Like “,*” Or sInput Like “*,” Then GoTo Bad
sNumbers = Split(sInput, “,”)
For X = 0 To UBound(sNumbers)
If sNumbers(X) Like “*-*” Then
If sNumbers(X) Like “*-*-*” Then GoTo Bad
sRange = Split(sNumbers(X), “-”)
sNumbers(X) = “”
For Z = sRange(0) To sRange(1) Step Sgn(sRange(1) – sRange(0) + 0.1)
sNumbers(X) = sNumbers(X) & “,” & Z
Next
sNumbers(X) = Mid(sNumbers(X), 2)
End If
Next
PagesToPrint = Split(Join(sNumbers, “,”), “,”)
Exit Function
Bad:
PagesToPrint = Array()
MsgBox “”"” & sInput & “”"” & vbLf & vbLf & “The range of values you specified is incorrectly formed!”, vbCritical
End Function

One more reason to prefer regular expressions.

You still have errors. Pass your latest function “1,2,” and it returns {“1?,”2?,”"}. Your validity checking fails when SInput begins or ends with a comma.

If you really insist on using Like patterns, then at least use them optimally.

The 1st If check in prose:
- can contain only decimal numerals, hyphens and commas
- must start with a numeral
- must end with a numeral
- can’t have substrings of 2 or more hyphens or commas
- can’t have 2 or more hyphens between commas

>> your function dies on an untrapped error when passed “-” and returns {“”,”"} when passed “,”.

I agree about regular expressions, but the last time I worked with them was on a UNIX system in the late 1980s, so RegEx pattern construction capabilities are a little rusty. Beside, I would guess most people following threads on this formum have little or no experience with them, so my code offers them a wholly native VB solution for them to digest. As for the state machine… too much extra code for my tastes. I think the above oversights on my part are easily corrected along with an error I had in my originally posted code (where I did a string rather than numeric comparison in the 2nd “If” statement inside the loop (which screwed up comparing a range like 9-11). Here is my modified code…

Nothing beats regular expressions for text parsing and lexical validity testing. ‘Course it helps to get the regex right. My first re.Pattern statement should have been

You CAN check the validity of the input string without regular expressions by using a formal state machine. Not pretty, but a lot more robust than screwing around trying to use Like to match and exhaustive set of compound tokens.