Commenting constraints causes Internal Error

Problem: Adding a comment in the same style as the documentation to a constraints file leads to an Internal Error.

Expected behaviour: Commented constraints load or faulty comment syntax leads to Parsing/Syntax Error and/or commenting syntax for constraints is explained in documentation.

MWE:

• put the following in file and load. It works:

import webanno.custom.A_Event as Event;

Event {
	a_Type = "ProductService" ->
		b_Subtype="CancellationRecall" | b_Subtype="Launch" | b_Subtype="Trial" |
		c_Participant.role="ProductService" (!) | c_Participant.role="Owner_ProductService" (!);
	b_Subtype = "Trial" ->
		c_Participant.role="Trialer" (!);
}

• Add a comment to the previous file. On upload, it redirects you to Internal Error page:

import webanno.custom.A_Event as Event;

Event {
	// ProductService
	a_Type = "ProductService" ->
		b_Subtype="CancellationRecall" | b_Subtype="Launch" | b_Subtype="Trial" |
		c_Participant.role="ProductService" (!) | c_Participant.role="Owner_ProductService" (!);
	b_Subtype = "Trial" ->
		c_Participant.role="Trialer" (!);
}

[reckart]

I have already done a documentation update locally and will commit it any moment.

[reckart]

Re-opening this issue because a proper error message should be displayed instead of an internal error page. Working on this.