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108 lines
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<title>Lazy Strings In Python - Debugging with GDB</title>
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<div class="node">
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<a name="Lazy-Strings-In-Python"></a>
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<p>
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Next: <a rel="next" accesskey="n" href="Architectures-In-Python.html#Architectures-In-Python">Architectures In Python</a>,
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Previous: <a rel="previous" accesskey="p" href="Finish-Breakpoints-in-Python.html#Finish-Breakpoints-in-Python">Finish Breakpoints in Python</a>,
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<h5 class="subsubsection">23.2.2.32 Python representation of lazy strings</h5>
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<p><a name="index-lazy-strings-in-python-2427"></a><a name="index-gdb_002eLazyString-2428"></a>
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A <dfn>lazy string</dfn> is a string whose contents is not retrieved or
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encoded until it is needed.
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<p>A <code>gdb.LazyString</code> is represented in <span class="sc">gdb</span> as an
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<code>address</code> that points to a region of memory, an <code>encoding</code>
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that will be used to encode that region of memory, and a <code>length</code>
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to delimit the region of memory that represents the string. The
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difference between a <code>gdb.LazyString</code> and a string wrapped within
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a <code>gdb.Value</code> is that a <code>gdb.LazyString</code> will be treated
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differently by <span class="sc">gdb</span> when printing. A <code>gdb.LazyString</code> is
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retrieved and encoded during printing, while a <code>gdb.Value</code>
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wrapping a string is immediately retrieved and encoded on creation.
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<p>A <code>gdb.LazyString</code> object has the following functions:
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<div class="defun">
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— Function: <b>LazyString.value</b> ()<var><a name="index-LazyString_002evalue-2429"></a></var><br>
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<blockquote><p>Convert the <code>gdb.LazyString</code> to a <code>gdb.Value</code>. This value
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will point to the string in memory, but will lose all the delayed
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retrieval, encoding and handling that <span class="sc">gdb</span> applies to a
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<code>gdb.LazyString</code>.
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</p></blockquote></div>
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<div class="defun">
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— Variable: <b>LazyString.address</b><var><a name="index-LazyString_002eaddress-2430"></a></var><br>
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<blockquote><p>This attribute holds the address of the string. This attribute is not
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writable.
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</p></blockquote></div>
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<div class="defun">
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— Variable: <b>LazyString.length</b><var><a name="index-LazyString_002elength-2431"></a></var><br>
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<blockquote><p>This attribute holds the length of the string in characters. If the
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length is -1, then the string will be fetched and encoded up to the
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first null of appropriate width. This attribute is not writable.
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</p></blockquote></div>
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<div class="defun">
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— Variable: <b>LazyString.encoding</b><var><a name="index-LazyString_002eencoding-2432"></a></var><br>
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<blockquote><p>This attribute holds the encoding that will be applied to the string
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when the string is printed by <span class="sc">gdb</span>. If the encoding is not
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set, or contains an empty string, then <span class="sc">gdb</span> will select the
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most appropriate encoding when the string is printed. This attribute
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is not writable.
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</p></blockquote></div>
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<div class="defun">
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— Variable: <b>LazyString.type</b><var><a name="index-LazyString_002etype-2433"></a></var><br>
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<blockquote><p>This attribute holds the type that is represented by the lazy string's
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type. For a lazy string this is a pointer or array type. To
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resolve this to the lazy string's character type, use the type's
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<code>target</code> method. See <a href="Types-In-Python.html#Types-In-Python">Types In Python</a>. This attribute is not
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writable.
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</p></blockquote></div>
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