&gt; OTOH you kind of need hashes&#x2F;maps in the real world<p>Well, plists (foo bar baz quux) and alists ((foo . bar) (baz . quux)) or ((foo bar) (baz quux)) have provided good enough functionality for quite a long time.<p>&gt; And Unicode.<p>S-expressions can be Unicode: (edelweiß) is a perfectly valid s-expression.<p>&gt; And standard representations for the base datatypes.<p>Common Lisp&#x27;s extensively documented reader algorithm[1] contains standard read forms for symbols, strings, characters lists, integers, rational numbers, floats, complex numbers, pathnames, structs, comments, vectors, arrays, bitfields as well as some miscellaneous other types.<p>There&#x27;s no reason that it couldn&#x27;t be augmented with something like #{} for hashes (although this would require updating the standard: currently, those characters are reserved for the user; maybe #H{} instead?), #D&quot;2015-12-01&quot; for dates, #U&quot;<a href="http:&#x2F;&#x2F;www.example.com&#x2F;&quot;" rel="nofollow">http:&#x2F;&#x2F;www.example.com&#x2F;&quot;</a> for URLs and so forth.<p>This:<p><pre><code>    #{(title &quot;Example Scheme&quot;)
      (type &quot;object&quot;)
      (properties #{(first-name #{(type string)})
                    (last-name ${(type string)})
                    (age ${(description &quot;Age in years&quot;)
                           (type integer)
                           (minimum 0)})})
      (required #(first-name last-name))}
</code></pre>
seems a lot nicer to my eyes than:<p><pre><code>    {
            &quot;title&quot;: &quot;Example Schema&quot;,
            &quot;type&quot;: &quot;object&quot;,
            &quot;properties&quot;: {
                    &quot;firstName&quot;: {
                            &quot;type&quot;: &quot;string&quot;
                    },
                    &quot;lastName&quot;: {
                            &quot;type&quot;: &quot;string&quot;
                    },
                    &quot;age&quot;: {
                            &quot;description&quot;: &quot;Age in years&quot;,
                            &quot;type&quot;: &quot;integer&quot;,
                            &quot;minimum&quot;: 0
                    }
            },
            &quot;required&quot;: [&quot;firstName&quot;, &quot;lastName&quot;]
    }
</code></pre>
[1] <a href="http:&#x2F;&#x2F;www.lispworks.com&#x2F;documentation&#x2F;lw70&#x2F;CLHS&#x2F;Body&#x2F;02_b.htm" rel="nofollow">http:&#x2F;&#x2F;www.lispworks.com&#x2F;documentation&#x2F;lw70&#x2F;CLHS&#x2F;Body&#x2F;02_b.h...</a>