Seaching for a folder via scripting: regular expression problem

[ubacher]

I am trying to search for a folder starting with the following:
D:\Foto Cache\2014-10-18

I use:

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IMWS.get('v1/folders', {
  regexp: 'path,' + 'D:\\Foto Cache\\2014-10-18'
which returns an illegal reg exp error.

If I put instead: 'D:.{1}Foto Cache.{1}2018-01-31'    
it works.

A Bug? or am I doing something wrong?

[Mario]

Make sure you are escaping all characters which have a special meaning in regular expressions.
See the Perl Regexp references listed in the IMatch help for details.

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[ubacher]

Make sure you are escaping all characters which have a special meaning

backslash is a special character. If, however, I escape it i.e. \\ then I get the error message that it is
an illegal expression. Why?

Not accepted: D:\\Foto Cache\\2014-10-18

Accepted: D:.{1}Foto Cache.{1}2018-01-31
( where I have put .{1} just to pin down where the error is}

[Mario]

Is : not also a special character?

[ubacher]

I tried it on: regex101.com

it takes the ":" as literal.

and it finds D:\\Foto Cache\\2014-10-18 as correct.

[Mario]

Make sure you are using a PERL regexp tester, not one of the others.
I have no deeper knowledge about regexp and I can't debug this for you, sorry.
I only work here and when the Boost RegExp parser tells IMatch that the regexp is invalid, I return that result to your app.

I have currently no IMatch working so I cannot try this out my self. Open a bug report if you think that IMWS is wrong so I can schedule time for a later test.

[Mario]

The Perl docs say:

https://perldoc.perl.org/perlrebackslash.html

If the character following the backslash is an ASCII letter or an ASCII digit, then the sequence may be special; if so, it's listed below. A few letters have not been used yet, so escaping them with a backslash doesn't change them to be special. A future version of Perl may assign a special meaning to them, so if you have warnings turned on, Perl issues a warning if you use such a sequence. [1].

So you cannot simply use \\ when it is followed by an ASCII character. See the doc page above for all details.
If you want to match a full path, use the path parameter instead.

[ubacher]

I found the problem:
In javascript one has to escape the \ also, thus I had to double the escaping:
instead of D:\\Foto Cache\\2014-10-18
I needed
D:\\\\Foto Cache\\\\2014-10-18

to do this automatically I then used

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rootFolder.replace(/\\/g, '\\\\')

I knew about the need to escape in javascript and also the need to escape in reg-exp but I never put both together. Learned something.
I hope this will help others, otherwise I apologize for taking your time.

[Mario]

See