Escaping Doublequotes with Backslash Does not Work #urgent

[arp]

I use a “table creator” to create a list of rules which are then fed to a “rule-based row splitter (dictionary)”

The rules are of the form:

$colname$="somevalue"    TRUE

I have created this setup multiple times already and it is working fine. However, some of the string values I need to compare contain doublequotes. According to the official documentation, they need to be scaped using a backslash. I tried that in various permutations, but it always fails.

Error message:

ERROR Rule-based Row Splitter (Dictionary) 0:228      Execute failed: 
java.text.ParseException: Line: 306: Expected: =>
$value$="2\"" => TRUE

Rule formating, I’ve tried, all failed:

$colname$ = 5"
$colname$ = 5\"
$colname$ = "5""
$colname$ = "5\""

According to the docs, the last one should be the correct syntax but it also fails with the above error code. What am I doing wrong?

[armingrudd]

Hi,

If the column is a type of Number then you don’t need the double quotation marks.
$colname$ = 5
But if it’s a String then just simply input the double quotes without any backslashes like this:
$colname$ = "5"
This works if you are creating the rules in a table creator node.
If you were creating rules in some node like string manipulation using some function like join, then you would need backslashes before each mark surrounding the value ($colname$ = \"5\").

Best,
Armin

[arp]

You didn’t understand my question. To clarify:
I am not interested in matching 5 but 5". So $colname$ = "5" doesn’t help me.

According to docs, the solution to my problem is $colname$ = "5\"" but it isn’t working. Either this is a bug or the documentation is incomplete/outdated. I assume there is some non-standard way to describe this, because a single equals sign is not commonly used to compare two values. Must be something KNIME specific that isn’t obvious and I’d like to know what it is.

[armingrudd]

Oh, Sorry.
In that case you have to use slashes instead of surrounding double quotes:
$colname$ = /5"/

Best,
Armin

PS:

@arp

or the documentation is incomplete/outdated

[arp]

I have slashes in the strings as well. I got it to work by writing a piece of python code. Thanks for pointing me in the right direction.

[armingrudd]

@arp

I have slashes in the strings as well

For those slashes inside your string you can use a backslash to escape.
For example if you have a string like this:
5"some text/some other text/some other text
Then the rule would be like this:
$colname$ = /5"some text\/some other text\/some other text/

Best,
Armin