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<a name="Lazy-Strings-In-Guile"></a>
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<a name="Guile-representation-of-lazy-strings_002e"></a>
<h4 class="subsubsection">23.3.3.20 Guile representation of lazy strings.</h4>

<a name="index-lazy-strings-in-guile"></a>
<a name="index-_003cgdb_003alazy_002dstring_003e"></a>

<p>A <em>lazy string</em> is a string whose contents is not retrieved or
encoded until it is needed.
</p>
<p>A <code>&lt;gdb:lazy-string&gt;</code> is represented in <small>GDB</small> as an
<code>address</code> that points to a region of memory, an <code>encoding</code>
that will be used to encode that region of memory, and a <code>length</code>
to delimit the region of memory that represents the string.  The
difference between a <code>&lt;gdb:lazy-string&gt;</code> and a string wrapped within
a <code>&lt;gdb:value&gt;</code> is that a <code>&lt;gdb:lazy-string&gt;</code> will be treated
differently by <small>GDB</small> when printing.  A <code>&lt;gdb:lazy-string&gt;</code> is
retrieved and encoded during printing, while a <code>&lt;gdb:value&gt;</code>
wrapping a string is immediately retrieved and encoded on creation.
</p>
<p>The following lazy-string-related procedures are provided by the
<code>(gdb)</code> module:
</p>
<dl>
<dt><a name="index-lazy_002dstring_003f"></a>Scheme Procedure: <strong>lazy-string?</strong> <em>object</em></dt>
<dd><p>Return <code>#t</code> if <var>object</var> is an object of type <code>&lt;gdb:lazy-string&gt;</code>.
Otherwise return <code>#f</code>.
</p></dd></dl>

<dl>
<dt><a name="index-lazy_002dstring_002daddress"></a>Scheme Procedure: <strong>lazy-string-address</strong> <em>lazy-sring</em></dt>
<dd><p>Return the address of <var>lazy-string</var>.
</p></dd></dl>

<dl>
<dt><a name="index-lazy_002dstring_002dlength"></a>Scheme Procedure: <strong>lazy-string-length</strong> <em>lazy-string</em></dt>
<dd><p>Return the length of <var>lazy-string</var> in characters.  If the
length is -1, then the string will be fetched and encoded up to the
first null of appropriate width.
</p></dd></dl>

<dl>
<dt><a name="index-lazy_002dstring_002dencoding"></a>Scheme Procedure: <strong>lazy-string-encoding</strong> <em>lazy-string</em></dt>
<dd><p>Return the encoding that will be applied to <var>lazy-string</var>
when the string is printed by <small>GDB</small>.  If the encoding is not
set, or contains an empty string,  then <small>GDB</small> will select the
most appropriate encoding when the string is printed.
</p></dd></dl>

<dl>
<dt><a name="index-lazy_002dstring_002dtype"></a>Scheme Procedure: <strong>lazy-string-type</strong> <em>lazy-string</em></dt>
<dd><p>Return the type that is represented by <var>lazy-string</var>&rsquo;s type.
For a lazy string this is a pointer or array type.  To
resolve this to the lazy string&rsquo;s character type, use <code>type-target-type</code>.
See <a href="Types-In-Guile.html#Types-In-Guile">Types In Guile</a>.
</p></dd></dl>

<dl>
<dt><a name="index-lazy_002dstring_002d_003evalue"></a>Scheme Procedure: <strong>lazy-string-&gt;value</strong> <em>lazy-string</em></dt>
<dd><p>Convert the <code>&lt;gdb:lazy-string&gt;</code> to a <code>&lt;gdb:value&gt;</code>.  This value
will point to the string in memory, but will lose all the delayed
retrieval, encoding and handling that <small>GDB</small> applies to a
<code>&lt;gdb:lazy-string&gt;</code>.
</p></dd></dl>

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