Can `gradethis::grade_this` use checks on the provided code (not the evaluated results)

[RaymondBalise]

I know I can test for an exact match on a student's code using grade_this_code() but is there a way to check for an exact match on what was typed as an answer on the code using grade_this().

I am working on teaching students about the type of vectors used by R. I want students to use typeof() to realize that R returns the major version of R as a character string (because it is a number that will not be used for math):

```{r ex2-typeof-solution, exercise.reveal_solution = TRUE}
typeof(R.version$major)
```

I see students providing: typeof(R.version$nickname) as a solution. That, like the correct answer of typeof(R.version$major), returns a character string. So it is being called a correct answer.

Is there a way to trap the case that students type a specific response inside of grade_this()? I think you can see what I am getting at using this code

```{r ex2-typeof-check}
grade_this({
  # I want to see if they typed this text
  fail_if_equal(.user_code == "typeof(R.version$nickname)", 
    message = "You are checking the nickname you want to be checking the major"
  )
  pass_if_equal(typeof(R.version$major), 
    message = "Interesting the version number is being treated as a character string. R does not want you to do math on the version number."
  )
  fail_if_equal(R.version$major,
    message = "Your code is telling you the major version. You want to check the type using `typeof()`."              
  )
  fail_if_equal(R.version,
    message = "That code tells you everything about the R version. Add a `$` and the key word for the `major` version."              
  )  
  fail(message = "Not quite. Take a peek at the hints!")
})
```

I see that .user_code captures the provided text but I don't see how to use it in a logic check.