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Copy file name to clipboardExpand all lines: clojure+/print/objects_and_protocols.html
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<spanid="cb1-2"><ahref="#cb1-2" aria-hidden="true" tabindex="-1"></a> (<spanclass="va">#'clojure.core/print-object</span> x w))</span></code><buttontitle="Copy to Clipboard" class="code-copy-button"><iclass="bi"></i></button></pre></div>
<p>The syntax is <code>#object[CLASS-NAME HASH toString())]</code> and as you can see, the toString of an Object is <code>CLASS-NAME@HASH</code>. This can get pretty ugly:</p>
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<divclass="sourceCode" id="cb5"><preclass="sourceCode clojure code-with-copy"><codeclass="sourceCode clojure"><spanid="cb5-1"><ahref="#cb5-1" aria-hidden="true" tabindex="-1"></a>(async/chan)</span></code><buttontitle="Copy to Clipboard" class="code-copy-button"><iclass="bi"></i></button></pre></div>
<spanid="cb1-2"><ahref="#cb1-2" aria-hidden="true" tabindex="-1"></a> (<spanclass="va">#'clojure.core/print-object</span> x w))</span></code><buttontitle="Copy to Clipboard" class="code-copy-button"><iclass="bi"></i></button></pre></div>
<p>The syntax is <code>#object[CLASS-NAME HASH toString())]</code> and as you can see, the toString of an Object is <code>CLASS-NAME@HASH</code>. For most objects this becomes quite a long string.</p>
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<divclass="sourceCode" id="cb5"><preclass="sourceCode clojure code-with-copy"><codeclass="sourceCode clojure"><spanid="cb5-1"><ahref="#cb5-1" aria-hidden="true" tabindex="-1"></a>(async/chan)</span></code><buttontitle="Copy to Clipboard" class="code-copy-button"><iclass="bi"></i></button></pre></div>
<p>It’s quite easy to miss the fact that it is a function as we are looking for a tiny little <code>fn</code> in a sea of text. If, like me, you are fond of the <ahref="../../code_interview/beating/with_stupid_stuff/z_combinator_gambit.html">odd lambda calculus excursion</a>, things get even more hectic.</p>
<p>Yikes! what an eyesore. This is not an academic issue specific to lambda calculus. Any function created from inside a function is helpfully identifiable through the <code>fn$fn</code> nesting. We create these quite regularly, and they are often printed in stack traces. I’m sure you have seen them when you map an inline function across a seq, and there is a bug in the anonymous function.</p>
class code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_SINGLEQUOTE_\)</span>fn__70990 cannot be cast to class clojure.lang.IPersistentCollection (code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_SINGLEQUOTE_\)</span>fn__70990 is in unnamed module of loader clojure.lang.DynamicClassLoader <spanclass="citation" data-cites="4b15f195">@4b15f195</span>; clojure.lang.IPersistentCollection is in unnamed module of loader ‘app’)
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class code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_SINGLEQUOTE_\)</span>fn__70990 cannot be cast to class clojure.lang.IPersistentCollection (code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_SINGLEQUOTE_\)</span>fn__70990 is in unnamed module of loader clojure.lang.DynamicClassLoader <spanclass="citation" data-cites="5ce97be8">@5ce97be8</span>; clojure.lang.IPersistentCollection is in unnamed module of loader ‘app’)
class code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_LOGIC\)</span>fn__71000 cannot be cast to class clojure.lang.IPersistentCollection (code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_LOGIC\)</span>fn__71000 is in unnamed module of loader clojure.lang.DynamicClassLoader <spanclass="citation" data-cites="38e0f0b7">@38e0f0b7</span>; clojure.lang.IPersistentCollection is in unnamed module of loader ‘app’)
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class code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_LOGIC\)</span>fn__71000 cannot be cast to class clojure.lang.IPersistentCollection (code_interview.beating.with_stupid_stuff.z_combinator_gambit<spanclass="math inline">\(REV_LOGIC\)</span>fn__71000 is in unnamed module of loader clojure.lang.DynamicClassLoader <spanclass="citation" data-cites="3a57de2e">@3a57de2e</span>; clojure.lang.IPersistentCollection is in unnamed module of loader ‘app’)
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