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| author | Craig Jennings <c@cjennings.net> | 2025-08-14 22:58:58 -0500 |
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| committer | Craig Jennings <c@cjennings.net> | 2025-08-14 22:58:58 -0500 |
| commit | 82ba818ff456bcd6d56a06226e3f27e98fbb55c3 (patch) | |
| tree | 158cfc17b2f644a10f063cb546752cfaae12c97f /devdocs/elisp/list_002drelated-predicates.html | |
| parent | 9278ddd4ea1a8b1a4c1edaa8894516e3f48d245b (diff) | |
| download | dotemacs-82ba818ff456bcd6d56a06226e3f27e98fbb55c3.tar.gz dotemacs-82ba818ff456bcd6d56a06226e3f27e98fbb55c3.zip | |
removing all downloaded devdocs files
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| -rw-r--r-- | devdocs/elisp/list_002drelated-predicates.html | 45 |
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diff --git a/devdocs/elisp/list_002drelated-predicates.html b/devdocs/elisp/list_002drelated-predicates.html deleted file mode 100644 index 03c7692e..00000000 --- a/devdocs/elisp/list_002drelated-predicates.html +++ /dev/null @@ -1,45 +0,0 @@ - <h3 class="section">Predicates on Lists</h3> <p>The following predicates test whether a Lisp object is an atom, whether it is a cons cell or is a list, or whether it is the distinguished object <code>nil</code>. (Many of these predicates can be defined in terms of the others, but they are used so often that it is worth having them.) </p> <dl> <dt id="consp">Function: <strong>consp</strong> <em>object</em> -</dt> <dd><p>This function returns <code>t</code> if <var>object</var> is a cons cell, <code>nil</code> otherwise. <code>nil</code> is not a cons cell, although it <em>is</em> a list. </p></dd> -</dl> <dl> <dt id="atom">Function: <strong>atom</strong> <em>object</em> -</dt> <dd> -<p>This function returns <code>t</code> if <var>object</var> is an atom, <code>nil</code> otherwise. All objects except cons cells are atoms. The symbol <code>nil</code> is an atom and is also a list; it is the only Lisp object that is both. </p> <div class="example"> <pre class="example">(atom <var>object</var>) ≡ (not (consp <var>object</var>)) -</pre> -</div> </dd> -</dl> <dl> <dt id="listp">Function: <strong>listp</strong> <em>object</em> -</dt> <dd> -<p>This function returns <code>t</code> if <var>object</var> is a cons cell or <code>nil</code>. Otherwise, it returns <code>nil</code>. </p> <div class="example"> <pre class="example">(listp '(1)) - ⇒ t -</pre> -<pre class="example">(listp '()) - ⇒ t -</pre> -</div> </dd> -</dl> <dl> <dt id="nlistp">Function: <strong>nlistp</strong> <em>object</em> -</dt> <dd> -<p>This function is the opposite of <code>listp</code>: it returns <code>t</code> if <var>object</var> is not a list. Otherwise, it returns <code>nil</code>. </p> <div class="example"> <pre class="example">(listp <var>object</var>) ≡ (not (nlistp <var>object</var>)) -</pre> -</div> </dd> -</dl> <dl> <dt id="null">Function: <strong>null</strong> <em>object</em> -</dt> <dd> -<p>This function returns <code>t</code> if <var>object</var> is <code>nil</code>, and returns <code>nil</code> otherwise. This function is identical to <code>not</code>, but as a matter of clarity we use <code>null</code> when <var>object</var> is considered a list and <code>not</code> when it is considered a truth value (see <code>not</code> in <a href="combining-conditions">Combining Conditions</a>). </p> <div class="example"> <pre class="example">(null '(1)) - ⇒ nil -</pre> -<pre class="example">(null '()) - ⇒ t -</pre> -</div> </dd> -</dl> <dl> <dt id="proper-list-p">Function: <strong>proper-list-p</strong> <em>object</em> -</dt> <dd> -<p>This function returns the length of <var>object</var> if it is a proper list, <code>nil</code> otherwise (see <a href="cons-cells">Cons Cells</a>). In addition to satisfying <code>listp</code>, a proper list is neither circular nor dotted. </p> <div class="example"> <pre class="example">(proper-list-p '(a b c)) - ⇒ 3 -</pre> -<pre class="example">(proper-list-p '(a b . c)) - ⇒ nil -</pre> -</div> </dd> -</dl><div class="_attribution"> - <p class="_attribution-p"> - Copyright © 1990-1996, 1998-2022 Free Software Foundation, Inc. <br>Licensed under the GNU GPL license.<br> - <a href="https://www.gnu.org/software/emacs/manual/html_node/elisp/List_002drelated-Predicates.html" class="_attribution-link">https://www.gnu.org/software/emacs/manual/html_node/elisp/List_002drelated-Predicates.html</a> - </p> -</div> |
