>From Fear of Macros again, all input in the DrRacket definition window.

This works:

#lang racket/base

(require (for-syntax racket/base))

(define-syntax (show-me stx)
  (display stx)
  #'(void))

If you mouse-hover over the keywords, define-syntax is imported from #lang 
racket/base, and display and #' are imported (require (for-syntax racket/base)).
Because display and #' are needed at compile time, not run time.

Therefore, logically, this doesn't work:

#lang racket/base

(define-syntax (show-me stx)
  (display stx)
  #'(void))

Gives the error: 
display: unbound identifier in the transformer environment; also, no #%app 
syntax transformer is bound in: display
And if we remove the display statement, the same error for #'

So far so good.

BUT

Why does this work?

#lang racket

(define-syntax (show-me stx)
  (display stx)
  #'(void))

Now define-syntax *and* display *and* #' are directly imported from #lang 
racket. What about compile time vs run time? What does #lang racket do apart 
from including many libraries on top of racket/base?

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