StringRegExp with optionals

[PrimeMover]

I'm trying to parse a filename that has an incremental number in it, for organizing media files. I've been trying to use StringRegExp to perform the procedure, but I've been having problems with designating optionals. The tutorials say that optionals are created by putting a "?" after a group, but every time I do it, the optional match completely ceases to function. Let me start over with what I'm doing. Here's a possible string:

'Exterior Store Pan (03).MP4'

I want to separate the string into three different componants: the name, the incremend number and the extension. Here are the conditions

1. The incremental number may or may not exist

2. The number match needs to remove the parenthesis

3. There may or may not be a space before the number, if so, it needs to be removed from the name match

4. other parenthetical text may appear before the number, in the name, and must be evaluated as part of the name

The problem is, I'm having real trouble with these optional statements. I'm using (.*) to capture everything up to the parenthesis, but if the parenthesis doesn't exist, the function errors. Also, I don't know how to capture only a parenthesis with numbers in it. I understand all the basics of creating matches, but with this conditionals, everything becomes quite baffling. I want to make this program very dummy proof, and able to evaluate any number of strange formats, within reason.

Any help would be much appreciated.

[Melba23]

PrimeMover,

I would forget trying to get it all in one SRE - although no doubt one of the gurus will be along shortly to show you how.

Why not do it in several steps like this:

Global $aName[4] = ["Exterior Store Pan (03).MP4", "Exterior (Store) Pan.MP4", "Exterior Store Pan ( 07).MP4", "Exterior (Store) Pan ( 02).mp4"]

For $i = 0 To UBound($aName) - 1

    ; Is there an incremental number in parentheses with a possible space before it
    If StringRegExp($aName[$i], "(s?d+)") Then
        ; The name runs to the final (
        $sName = StringRegExpReplace($aName[$i], "(.*)(.*", "$1")
        ; The number is in the final set of () - and we remove any white space aftrewards
        $sNumber = StringStripWS(StringRegExpReplace($aName[$i], ".*((.+)).*", "$1"), 1)
    Else
        ; The name runs to the .ext
        $sName = StringRegExpReplace($aName[$i], "(.*)..*", "$1")
        ; There is no incremental number
        $sNumber = ""
    EndIf
    ; And teh extension is always after the final .
    $sExt = StringRegExpReplace($aName[$i], ".*.(.+)", "$1")

    ; And here are the results
    MsgBox(0, "Result", $sName & @CRLF & $sNumber & @CRLF & $sExt)

Next

Good enough? Let me know if you find a format that does not work.

M23

[PrimeMover]

Thanks! That did it! Yeah, a lot better than trying to actually use optionals. I was so stuck in a rut, I didn't think about doing it the more conventional way.

[Melba23]

PrimeMover,

a lot better than trying to actually use optionals

Actually there is an optional in there:

StringRegExp($aName[$i], "(s?d+)") ;  s? = a space which may or may not be there

I often fall foul of the "all in one SRE" syndrome. You want the optimal solution and get too complicated - which is always fatal!

Glad I could help.

M23

[jchd]

Let me a chance. I take specification 4) as meaning something like

Exterior Store (pink) Pan (03).MP4

Then from what I understand you can use the following :

$res= StringRegExp($aName[$i], "^(.*?)(?:(?:s*((d+)))?(..*))$", 1)

You should get your 3 components as $res[0] to $res[2]

This worked on the following inputs:

Exterior Store Pan.MP4
Exterior Store Pan (03).MP4
Exterior Store (pink) Pan.MP4
Exterior Store (pink) Pan (03).MP4
Exterior (strong) Store type (03) color (pink) Pan (03).MP4

Note that it will fail on "Exterior (strong) Store model abc (05).mp4 type (03) color (pink) Pan (03).MP4"

Given that the last sentence "I want to make this program very dummy proof, and able to evaluate any number of strange formats, within reason." opens a wide room for madness, I won't consider that a problem. If you need that anyway, it can still be dealt with.

[Melba23]

jchd,

I just knew a real guru would do it in one!

M23

[jchd]

This one is fairly simple compared to what can be seen elsewhere.

Long ago I could have done it as a one-liner really supercryptic APL but PLEASE don't ask now!