the call/cc "yin-yang" puzzle's execution expanded

yin-yang-expanded.scm

(let* ((yin
         ((lambda (cc) (display #\@) cc) (call-with-current-continuation (lambda (c) c))))
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))


snapshot A:
(let* ((yin
         ((lambda (cc) (display #\@) cc) _))
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))

@

(let* ((yin A)
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))
(let* ((yin A)
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))
         
which is the same as:
(let ((yang
        ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (A yang))

snapshot B:
(let ((yang
        ((lambda (cc) (display #\*) cc) _)))
    (A yang))

*

(let ((yang B))
    (A yang))
(A B)

(let* ((yin
         ((lambda (cc) (display #\@) cc) B))
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))

@

(let ([yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))])
	(B yang))
	
snapshot B':
(let ([yang
         ((lambda (cc) (display #\*) cc) _)])
	(B yang))
	
*

(B B')

(let ((yang
        ((lambda (cc) (display #\*) cc) B')))
    (A yang))
	
*

(A B')
(let* ((yin
         ((lambda (cc) (display #\@) cc) B'))
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))
	
@

(let ((yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
	(B' yang))
	
snapshot B'':
(let ((yang
         ((lambda (cc) (display #\*) cc) _)))
	(B' yang))

*

(B' B'')

(let ([yang
         ((lambda (cc) (display #\*) cc) B'')])
	(B yang))
	
*

(B B'')

(let ((yang
        ((lambda (cc) (display #\*) cc) B'')))
    (A yang))
	
*

(A B'')

(let* ((yin
         ((lambda (cc) (display #\@) cc) B''))
       (yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (yin yang))
	
@

(let* ((yang
         ((lambda (cc) (display #\*) cc) (call-with-current-continuation (lambda (c) c)))))
    (B'' yang))

snapshot B''':
(let* ((yang
         ((lambda (cc) (display #\*) cc) _)))
    (B'' yang))

*

(B'' B''')

...

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