please add check for '+-', '-', '/', '-/', '+-', '+-/' and other same strings! because in some solution have "... if op in '+-/' else ..." and if i take (1, 5, '+-') it's will be a mistake exception!!!

What is it?

There is something wrong

Reading the error message would help to debug and fix your code:

Your function should be able to handle floats
Failed asserting that 'unknown value' matches expected 1.
Expected: 1
Actual  : unknown value

Your code returns "unknown value" for floats, it's your code's problem, not a kata issue.

It's not an issue if you don't tell us what the "issue" is!

If you really think there is an issue, then please provide the language in question, and description about how the kata is wrong. Is there a specific test that is wrong, or some kind of error you're getting?

Closing due to lack of information. Please read the documentation available before creating issues like this, for example https://docs.codewars.com/training/troubleshooting

there is an isuue in this problem

Question resolved.

Not a kata suggestion. Resolved.

The error you see happens before the check. The error is raised in line 2, and your check is too late, in line 3.

It's a bug in your solution, not a kata issue.

That's a problem with your code, not with the kata.

I don't get it ? ...isn't supposed to be simple fundamentals ?
I write in JS so typeof is default XD

Can someone with edit abilities please add the following 3 tests to the Error Test Cases section. Currently this specific test is only being done for +, not the other operators, and it's allowed some solutions to get through (and be highly upvoted) that don't actually meet all the requirments in the description.

test.assert_equals(calculator(":", ",", '-'),"unknown value")
test.assert_equals(calculator(":", ",", '*'),"unknown value")
test.assert_equals(calculator(":", ",", '/'),"unknown value")