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<span id="string_003d"></span><div class="header">
<p>
Next: <a href="stringp.html" accesskey="n" rel="next">stringp</a>, Previous: <a href="string_002dtrim.html" accesskey="p" rel="prev">string-trim</a>, Up: <a href="Strings-Dictionary.html" accesskey="u" rel="up">Strings Dictionary</a> </p>
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<span id="string_003d_002c-string_002f_003d_002c-string_003c_002c-string_003e_002c-string_003c_003d_002c-string_003e_003d_002c"></span><h4 class="subsection">16.2.10 string=, string/=, string<, string>, string<=, string>=,</h4>
<span id="string_002dequal_002c-string_002dnot_002dequal_002c-string_002dlessp_002c"></span><h4 class="subheading">string-equal, string-not-equal, string-lessp,</h4>
<span id="string_002dgreaterp_002c-string_002dnot_002dgreaterp_002c-string_002dnot_002dlessp"></span><h4 class="subheading">string-greaterp, string-not-greaterp, string-not-lessp</h4>
<p align="right"><i>[Function]</i>
</p>
<p><code>string=</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>generalized-boolean</i>
</p>
<p><code>string/=</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string<</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string></code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string<=</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string>=</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string-equal</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>generalized-boolean</i>
</p>
<p><code>string-not-equal</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string-lessp</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string-greaterp</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string-not-greaterp</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<p><code>string-not-lessp</code> <i>string1 string2 <span class="roman">&key</span> start1 end1 start2 end2</i> ⇒ <i>mismatch-index</i>
</p>
<span id="Arguments-and-Values_003a_003a-351"></span><h4 class="subsubheading">Arguments and Values::</h4>
<p><i>string1</i>—a <i>string designator</i>.
</p>
<p><i>string2</i>—a <i>string designator</i>.
</p>
<p><i>start1</i>, <i>end1</i>—<i>bounding index designators</i> of <i>string1</i>.
The defaults for <i>start</i> and <i>end</i> are <tt>0</tt> and <b>nil</b>, respectively.
</p>
<p><i>start2</i>, <i>end2</i>—<i>bounding index designators</i> of <i>string2</i>.
The defaults for <i>start</i> and <i>end</i> are <tt>0</tt> and <b>nil</b>, respectively.
</p>
<p><i>generalized-boolean</i>—a <i>generalized boolean</i>.
</p>
<p><i>mismatch-index</i>—a <i>bounding index</i> of <i>string1</i>, or <b>nil</b>.
</p>
<span id="Description_003a_003a-465"></span><h4 class="subsubheading">Description::</h4>
<p>These functions perform lexicographic comparisons on <i>string1</i> and <i>string2</i>.
<b>string=</b> and <b>string-equal</b> are called equality functions;
the others are called inequality functions.
The comparison operations these <i>functions</i> perform are restricted
to the subsequence of <i>string1</i> <i>bounded</i> by <i>start1</i> and <i>end1</i>
and to the subsequence of <i>string2</i> <i>bounded</i> by <i>start2</i> and <i>end2</i>.
</p>
<p>A string <i>a</i> is equal to a string <i>b</i> if it contains the same number
of characters, and the corresponding characters are the <i>same</i>
under <b>char=</b> or <b>char-equal</b>, as appropriate.
</p>
<p>A string <i>a</i> is less than a string <i>b</i> if in the first position in
which they differ the character of <i>a</i> is less than the corresponding
character of <i>b</i> according to <b>char<</b> or <b>char-lessp</b>
as appropriate, or if string <i>a</i> is a proper prefix of string <i>b</i>
(of shorter length and matching in all the characters of <i>a</i>).
</p>
<p>The equality functions return a <i>generalized boolean</i>
that is <i>true</i> if the strings are equal,
or <i>false</i> otherwise.
</p>
<p>The inequality functions return a <i>mismatch-index</i>
that is <i>true</i> if the strings are not equal,
or <i>false</i> otherwise.
When the <i>mismatch-index</i> is <i>true</i>,
it is an <i>integer</i> representing the first character position at which the
two substrings differ, as an offset from the beginning of <i>string1</i>.
</p>
<p>The comparison has one of the following results:
</p>
<dl compact="compact">
<dt><b>string=</b></dt>
<dd><p><b>string=</b> is <i>true</i> if the supplied substrings are of
the same length and contain the <i>same</i> characters in corresponding
positions; otherwise it is <i>false</i>.
</p>
</dd>
<dt><b>string/=</b></dt>
<dd><p><b>string/=</b> is <i>true</i> if the supplied substrings are
different; otherwise it is <i>false</i>.
</p>
</dd>
<dt><b>string-equal</b></dt>
<dd><p><b>string-equal</b> is just like <b>string=</b>
except that differences in case are ignored;
two characters are considered to be the same if <b>char-equal</b> is <i>true</i> of them.
</p>
</dd>
<dt><b>string<</b></dt>
<dd><p><b>string<</b> is <i>true</i> if substring1 is less than substring2;
otherwise it is <i>false</i>.
</p>
</dd>
<dt><b>string></b></dt>
<dd><p><b>string></b> is <i>true</i> if substring1 is greater than substring2;
otherwise it is <i>false</i>.
</p>
</dd>
<dt><b>string-lessp</b>, <b>string-greaterp</b></dt>
<dd><p><b>string-lessp</b> and <b>string-greaterp</b>
are exactly like <b>string<</b> and <b>string></b>, respectively,
except that distinctions between uppercase and lowercase letters are ignored.
It is as if <b>char-lessp</b> were used instead of <b>char<</b>
for comparing characters.
</p>
</dd>
<dt><b>string<=</b></dt>
<dd><p><b>string<=</b> is <i>true</i> if substring1 is less than or equal to substring2;
otherwise it is <i>false</i>.
</p>
</dd>
<dt><b>string>=</b></dt>
<dd><p><b>string>=</b> is <i>true</i> if substring1 is greater than or equal to substring2;
otherwise it is <i>false</i>.
</p>
</dd>
<dt><b>string-not-greaterp</b>, <b>string-not-lessp</b></dt>
<dd><p><b>string-not-greaterp</b> and <b>string-not-lessp</b>
are exactly like <b>string<=</b> and <b>string>=</b>, respectively,
except that distinctions between uppercase and lowercase letters are ignored.
It is as if <b>char-lessp</b> were used instead of <b>char<</b>
for comparing characters.
</p>
</dd>
</dl>
<span id="Examples_003a_003a-333"></span><h4 class="subsubheading">Examples::</h4>
<div class="example">
<pre class="example"> (string= "foo" "foo") ⇒ <i>true</i>
(string= "foo" "Foo") ⇒ <i>false</i>
(string= "foo" "bar") ⇒ <i>false</i>
(string= "together" "frog" :start1 1 :end1 3 :start2 2) ⇒ <i>true</i>
(string-equal "foo" "Foo") ⇒ <i>true</i>
(string= "abcd" "01234abcd9012" :start2 5 :end2 9) ⇒ <i>true</i>
(string< "aaaa" "aaab") ⇒ 3
(string>= "aaaaa" "aaaa") ⇒ 4
(string-not-greaterp "Abcde" "abcdE") ⇒ 5
(string-lessp "012AAAA789" "01aaab6" :start1 3 :end1 7
:start2 2 :end2 6) ⇒ 6
(string-not-equal "AAAA" "aaaA") ⇒ <i>false</i>
</pre></div>
<span id="See-Also_003a_003a-379"></span><h4 class="subsubheading">See Also::</h4>
<p><a href="char_003d.html">char=</a>
</p>
<span id="Notes_003a_003a-254"></span><h4 class="subsubheading">Notes::</h4>
<p><b>equal</b> calls <b>string=</b> if applied to two <i>strings</i>.
</p>
<hr>
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<p>
Next: <a href="stringp.html" accesskey="n" rel="next">stringp</a>, Previous: <a href="string_002dtrim.html" accesskey="p" rel="prev">string-trim</a>, Up: <a href="Strings-Dictionary.html" accesskey="u" rel="up">Strings Dictionary</a> </p>
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