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copied!<p>There are a few basic mistakes/problems. But with only two small changes we can get your example to work in Common Lisp.</p> <ul> <li><p>Emacs Lisp's compatibility package for Common Lisp is not really a Common Lisp. It is generally preferable to use a real Common Lisp implementation. Emacs Lisp lacks a few basic things that are hard to emulate to make it compatible with Common Lisp - for example <strong>lexical closures</strong> (update 2014, the latest version of GNU Emacs now also supports lexical closures).</p></li> <li><p>Minor change: I changed your example so that the database does not contain Steve Jobs twice, but Steve Jobs and Steve Ballmer.</p></li> </ul> <p>Now, what would we need to change to make it work in Common Lisp?</p> <ul> <li><p>(getf employee :first-name) should really be (employee-first-name employee) . The DEFSTRUCT macro generates these accessor functions automatically. In Common Lisp you can't use GETF to access the fields of real structures.</p></li> <li><p>Your database has two objects with the name STEVE (a symbol), but you are searching for the name "steve" (a string). (equal 'steve "steve") is false. In general a symbol is not EQUAL to a string. So you should search with (select-by-first 'steve).</p></li> </ul> <p>In LispWorks then:</p> <pre><code>CL-USER 11 > (select-by-first "steve") NIL CL-USER 12 > (select-by-first 'steve) (#S(EMPLOYEE :AGE 53 :FIRST-NAME STEVE :LAST-NAME BALLMER :SEX MALE :CHILDREN NIL) #S(EMPLOYEE :AGE 43 :FIRST-NAME STEVE :LAST-NAME JOBS :SEX MALE :CHILDREN NIL)) </code></pre>

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