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<h2>Full example</h2>
<pre><code>; Source: https://github.com/mbutterick/pollen/blob/master/pollen/private/to-string.rkt
#lang racket/base
(provide (all-defined-out))
(define (to-string x)
(cond
[(string? x) x]
[(or (null? x) (void? x)) ""]
[(or (symbol? x) (number? x) (path? x) (char? x)) (format "~a" x)]
;; special handling for procedures, because if a procedure reaches this func,
;; it usually indicates a failed attempt to use a tag function.
;; meaning, it's more useful to raise an error.
[(procedure? x) (error 'pollen "Can't convert procedure ~a to string" x)]
[else (format "~v" x)]))</code></pre>
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