Division sign (slash) is confused with multiline comment

Hello,

I listed below a snapshot of my rules for parsing binary operation:

binary_operation: sum_operation

sum_operation: mul_operation
    | sum_operation PLUS mul_operation  -> add
    | sum_operation MINUS mul_operation -> minus
    
mul_operation: power_operation      
    | mul_operation MULTIPLICATION power_operation  -> mul
    | mul_operation DIVISION power_operation        -> div
    
power_operation: new_expression
    | power_operation POWER expression  -> power

expression: constant
		| reference

reference: name
 
name: ID | quoted_identifier

ID: /[A-Za-z][A-Za-z0-9\d_]*/
	
PLUS: "+"
DIVISION: "/"
MINUS: "-"
POWER : "^"
MULTIPLICATION: "*"

MULTILINE_COMMENT: /\/\*.*?\*\//s

%ignore MULTILINE_COMMENT
%ignore /\s/s

The rules work well when parsing the expression:

x/**/:=/**/(1.00000000000000002E-02/**/*y)

But parsing the following expression results in the error below:

x/**/:=/**/(y/**// 4.0)

lark.exceptions.UnexpectedCharacters: No terminal defined for ‘/’ at line Expecting: {‘MINUS’, ‘PLUS’, ‘MULTIPLICATION’, ‘POWER’}

Any help would be much appreciated,

Best regards

[MegaIng]

Please give an MCVE. Your issue leads to a lot of open questions:

• The grammar isn’t complete. There are a few rules referenced that you didn’t post.
• Which parser did you use?
• Which lexer did you use?

I can also see that what you posted there can’t be the exact grammar you are using (or we have an incredible severe bug in Lark somewhere that should prevent most grammars from working). Otherwise DIVIDE would have to appear in the Expected list.

We are certainly ready and open to help you, but you didn’t give us enough information.

[erezsh]

I went with @MegaIng 's suggestion.

@khaled-ek @charles-esterbrook This is now fixed in master, and will be part of the next release.

Hopefully it won’t break anyone’s code.