A student's question

My teacher keeps drilling into our collective heads that using the break command is harmful, and that if we wish to terminate a loop early it would be far better to create a boolean variable, set it to 0, and add a condition to the head of the loop, and set the boolean variable to 1 when a break is needed. Note that this way you actually have to check this every single loop (where it is not needed almost every time) as well as waste a command to reset the boolean in case it was set to true.

Is there a reason to this?

Welcome to Racket v5.1.1.5.
#;> (define current-function
      (make-parameter #f))
#;>
    (define-syntax-rule (this-function)
      (object-name (current-function)))
#;>
    (define-syntax-rule (defun f args . body)
      (define (f . args)
        (parameterize ((current-function f))
          . body)))
#;>
    (defun f () (this-function))
#;> (f)
'f
#;>