Forum Discussion
Wildcard Matching 2024
Not mad at all. But I think what you are really looking for is implementation of wild cards in M code. You're doing that with your custom function. The JavaScript implementation is also a custom function using only functions that are available in M
, unlike the python or r implementations which require something external.
So I don't really see it as any more of a workaround than your custom function.
I agree the use of python or or might be considered a workaround since they require external libraries to be installed.
To their own, but the JavaScript implementation certainly does work in Excel, I have used it many times.
If you look back to my first post, I said my code did not work comparing "08erig1" and "*8*#*1" should give a FALSE as result.
You query did not work at all for that:
In real life I need a wildcard routine that has a very simple syntax because the end user specifies the mask. If I come to my customer with RegEx, he'll kick me out. No normal end user uses that, it's far too complicated to get the correct pattern.
* ? and # is pretty simple to use for everyone and that's what I'm after. My code works to filter filenames that contains names and years, but I know it's not perfect, there is a bug that I can't find.
I can't use calls to external libraries, I don't know if every end user really has that or if the admin has disabled it for security reasons. I need a solution in MCode, no detours.
To my 2nd question: Any hint how to post an MCode with recursive calls here and prevent this forum editor to modify the code?
Andreas.
Now that I realize the limitations of the person entering the mask, your post makes more sense. If it were me, I would write a routine that translates the user input into a valid JavaScript regex and then feed that into the regex function I posted.
So far as your second problem, I don't have a clue.I've yet to figure out what invalid HTML means in that context. Perhaps you could post a link to a text file that you've uploaded someplace.
- Unfortunately, I can't work on a conversion routine right now as my computer is having fits leaving unable to run programs from my main drive. I somehow am in the position of having to rebuild a raid 1 array from scratch unless someone comes up with an idea that circumvents that necessity.
I've looked around a bit and a conversion should be possible with a few small replacements.
One difficulty is that the dot in RegEx itself is a wildcard, all the sources I've found say you should use \. instead of . and if I want to ignore the spelling, I should append /i.
Everything else later and thus a simple test:
// fnRegEx let fx=(text,regex)=> Web.Page( "<script> var x='"&text&"'; var y=new RegExp('"®ex&"','g'); var b=x.match(y); document.write(b); </script>")[Data]{0}[Children]{0}[Children]{1}[Text]{0} in fx // Test_fnRegEx // Test_fnRegEx let a = fnRegEx("qweXxls", "qwe.xls"), // Result: qweXxls => wong b = fnRegEx("qweXxls", "qwe\.xls"), // Result: qweXxls => wrong c = fnRegEx("Qwe.xls", "qwe\.xls/i") // Result: null => wrong in cDoesn't even come close to working. What now?
Does the RegEx that we call with the script use a different syntax??Andreas.
Finally got my computer working.
For your three wild cards which I assume as similar meanings as the Like vba operator, something like:
(text,regex)=> let regList = Text.ToList(regex), translate = List.ReplaceMatchingItems(regList, List.Zip({{"*","#","?","."}, {".*","[0-9]",".","\\."}})), reg = Text.Combine(translate,""), fx = Web.Page( "<script> var x='"&text&"'; var y=new RegExp('"& reg &"','g'); var b=x.match(y); document.write(b); </script>")[Data]{0}[Children]{0}[Children]{1}[Text]{0} in fxResults
fnRegexExtr("08erig1", "*8*#*1") => null fnRegexExtr("qweXxls", "qwe.xls") => null