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| <h5 class="subsubsection">23.2.2.4 Types In Python</h5> |
| |
| <p><a name="index-types-in-Python-1623"></a><a name="index-Python_002c-working-with-types-1624"></a> |
| <a name="index-gdb_002eType-1625"></a><span class="sc">gdb</span> represents types from the inferior using the class |
| <code>gdb.Type</code>. |
| |
| <p>The following type-related functions are available in the <code>gdb</code> |
| module: |
| |
| <p><a name="index-gdb_002elookup_005ftype-1626"></a> |
| |
| <div class="defun"> |
| — Function: <b>lookup_type</b><var> name </var>[<var>block</var>]<var><a name="index-lookup_005ftype-1627"></a></var><br> |
| <blockquote><p>This function looks up a type by name. <var>name</var> is the name of the |
| type to look up. It must be a string. |
| |
| <p>If <var>block</var> is given, then <var>name</var> is looked up in that scope. |
| Otherwise, it is searched for globally. |
| |
| <p>Ordinarily, this function will return an instance of <code>gdb.Type</code>. |
| If the named type cannot be found, it will throw an exception. |
| </p></blockquote></div> |
| |
| <p>An instance of <code>Type</code> has the following attributes: |
| |
| <dl> |
| |
| <div class="defun"> |
| — Instance Variable of Type: <b>code</b><var><a name="index-code-1628"></a></var><br> |
| <blockquote> <p>The type code for this type. The type code will be one of the |
| <code>TYPE_CODE_</code> constants defined below. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Instance Variable of Type: <b>sizeof</b><var><a name="index-sizeof-1629"></a></var><br> |
| <blockquote> <p>The size of this type, in target <code>char</code> units. Usually, a |
| target's <code>char</code> type will be an 8-bit byte. However, on some |
| unusual platforms, this type may have a different size. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Instance Variable of Type: <b>tag</b><var><a name="index-tag-1630"></a></var><br> |
| <blockquote> <p>The tag name for this type. The tag name is the name after |
| <code>struct</code>, <code>union</code>, or <code>enum</code> in C and C<tt>++</tt>; not all |
| languages have this concept. If this type has no tag name, then |
| <code>None</code> is returned. |
| </p></blockquote></div> |
| </dl> |
| |
| <p>The following methods are provided: |
| |
| <dl> |
| |
| <div class="defun"> |
| — Method on Type: <b>fields</b><var><a name="index-fields-on-Type-1631"></a></var><br> |
| <blockquote> <p>For structure and union types, this method returns the fields. Range |
| types have two fields, the minimum and maximum values. Enum types |
| have one field per enum constant. Function and method types have one |
| field per parameter. The base types of C<tt>++</tt> classes are also |
| represented as fields. If the type has no fields, or does not fit |
| into one of these categories, an empty sequence will be returned. |
| |
| <p>Each field is an object, with some pre-defined attributes: |
| <dl> |
| <dt><code>bitpos</code><dd>This attribute is not available for <code>static</code> fields (as in |
| C<tt>++</tt> or Java). For non-<code>static</code> fields, the value is the bit |
| position of the field. |
| |
| <br><dt><code>name</code><dd>The name of the field, or <code>None</code> for anonymous fields. |
| |
| <br><dt><code>artificial</code><dd>This is <code>True</code> if the field is artificial, usually meaning that |
| it was provided by the compiler and not the user. This attribute is |
| always provided, and is <code>False</code> if the field is not artificial. |
| |
| <br><dt><code>is_base_class</code><dd>This is <code>True</code> if the field represents a base class of a C<tt>++</tt> |
| structure. This attribute is always provided, and is <code>False</code> |
| if the field is not a base class of the type that is the argument of |
| <code>fields</code>, or if that type was not a C<tt>++</tt> class. |
| |
| <br><dt><code>bitsize</code><dd>If the field is packed, or is a bitfield, then this will have a |
| non-zero value, which is the size of the field in bits. Otherwise, |
| this will be zero; in this case the field's size is given by its type. |
| |
| <br><dt><code>type</code><dd>The type of the field. This is usually an instance of <code>Type</code>, |
| but it can be <code>None</code> in some situations. |
| </dl> |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>array</b><var> n1 </var><span class="roman">[</span><var>n2</var><span class="roman">]</span><var><a name="index-array-on-Type-1632"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents an array of this |
| type. If one argument is given, it is the inclusive upper bound of |
| the array; in this case the lower bound is zero. If two arguments are |
| given, the first argument is the lower bound of the array, and the |
| second argument is the upper bound of the array. An array's length |
| must not be negative, but the bounds can be. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>const</b><var><a name="index-const-on-Type-1633"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents a |
| <code>const</code>-qualified variant of this type. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>volatile</b><var><a name="index-volatile-on-Type-1634"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents a |
| <code>volatile</code>-qualified variant of this type. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>unqualified</b><var><a name="index-unqualified-on-Type-1635"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents an unqualified |
| variant of this type. That is, the result is neither <code>const</code> nor |
| <code>volatile</code>. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>range</b><var><a name="index-range-on-Type-1636"></a></var><br> |
| <blockquote> <p>Return a Python <code>Tuple</code> object that contains two elements: the |
| low bound of the argument type and the high bound of that type. If |
| the type does not have a range, <span class="sc">gdb</span> will raise a |
| <code>RuntimeError</code> exception. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>reference</b><var><a name="index-reference-on-Type-1637"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents a reference to this |
| type. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>pointer</b><var><a name="index-pointer-on-Type-1638"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents a pointer to this |
| type. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>strip_typedefs</b><var><a name="index-strip_005ftypedefs-on-Type-1639"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> that represents the real type, |
| after removing all layers of typedefs. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>target</b><var><a name="index-target-on-Type-1640"></a></var><br> |
| <blockquote> <p>Return a new <code>gdb.Type</code> object which represents the target type |
| of this type. |
| |
| <p>For a pointer type, the target type is the type of the pointed-to |
| object. For an array type (meaning C-like arrays), the target type is |
| the type of the elements of the array. For a function or method type, |
| the target type is the type of the return value. For a complex type, |
| the target type is the type of the elements. For a typedef, the |
| target type is the aliased type. |
| |
| <p>If the type does not have a target, this method will throw an |
| exception. |
| </p></blockquote></div> |
| |
| <div class="defun"> |
| — Method on Type: <b>template_argument</b><var> n </var>[<var>block</var>]<var><a name="index-template_005fargument-on-Type-1641"></a></var><br> |
| <blockquote> <p>If this <code>gdb.Type</code> is an instantiation of a template, this will |
| return a new <code>gdb.Type</code> which represents the type of the |
| <var>n</var>th template argument. |
| |
| <p>If this <code>gdb.Type</code> is not a template type, this will throw an |
| exception. Ordinarily, only C<tt>++</tt> code will have template types. |
| |
| <p>If <var>block</var> is given, then <var>name</var> is looked up in that scope. |
| Otherwise, it is searched for globally. |
| </p></blockquote></div> |
| </dl> |
| |
| <p>Each type has a code, which indicates what category this type falls |
| into. The available type categories are represented by constants |
| defined in the <code>gdb</code> module: |
| |
| |
| <a name="index-TYPE_005fCODE_005fPTR-1642"></a> |
| <a name="index-gdb_002eTYPE_005fCODE_005fPTR-1643"></a> |
| <dl><dt><code>TYPE_CODE_PTR</code><dd>The type is a pointer. |
| |
| <p><a name="index-TYPE_005fCODE_005fARRAY-1644"></a><a name="index-gdb_002eTYPE_005fCODE_005fARRAY-1645"></a><br><dt><code>TYPE_CODE_ARRAY</code><dd>The type is an array. |
| |
| <p><a name="index-TYPE_005fCODE_005fSTRUCT-1646"></a><a name="index-gdb_002eTYPE_005fCODE_005fSTRUCT-1647"></a><br><dt><code>TYPE_CODE_STRUCT</code><dd>The type is a structure. |
| |
| <p><a name="index-TYPE_005fCODE_005fUNION-1648"></a><a name="index-gdb_002eTYPE_005fCODE_005fUNION-1649"></a><br><dt><code>TYPE_CODE_UNION</code><dd>The type is a union. |
| |
| <p><a name="index-TYPE_005fCODE_005fENUM-1650"></a><a name="index-gdb_002eTYPE_005fCODE_005fENUM-1651"></a><br><dt><code>TYPE_CODE_ENUM</code><dd>The type is an enum. |
| |
| <p><a name="index-TYPE_005fCODE_005fFLAGS-1652"></a><a name="index-gdb_002eTYPE_005fCODE_005fFLAGS-1653"></a><br><dt><code>TYPE_CODE_FLAGS</code><dd>A bit flags type, used for things such as status registers. |
| |
| <p><a name="index-TYPE_005fCODE_005fFUNC-1654"></a><a name="index-gdb_002eTYPE_005fCODE_005fFUNC-1655"></a><br><dt><code>TYPE_CODE_FUNC</code><dd>The type is a function. |
| |
| <p><a name="index-TYPE_005fCODE_005fINT-1656"></a><a name="index-gdb_002eTYPE_005fCODE_005fINT-1657"></a><br><dt><code>TYPE_CODE_INT</code><dd>The type is an integer type. |
| |
| <p><a name="index-TYPE_005fCODE_005fFLT-1658"></a><a name="index-gdb_002eTYPE_005fCODE_005fFLT-1659"></a><br><dt><code>TYPE_CODE_FLT</code><dd>A floating point type. |
| |
| <p><a name="index-TYPE_005fCODE_005fVOID-1660"></a><a name="index-gdb_002eTYPE_005fCODE_005fVOID-1661"></a><br><dt><code>TYPE_CODE_VOID</code><dd>The special type <code>void</code>. |
| |
| <p><a name="index-TYPE_005fCODE_005fSET-1662"></a><a name="index-gdb_002eTYPE_005fCODE_005fSET-1663"></a><br><dt><code>TYPE_CODE_SET</code><dd>A Pascal set type. |
| |
| <p><a name="index-TYPE_005fCODE_005fRANGE-1664"></a><a name="index-gdb_002eTYPE_005fCODE_005fRANGE-1665"></a><br><dt><code>TYPE_CODE_RANGE</code><dd>A range type, that is, an integer type with bounds. |
| |
| <p><a name="index-TYPE_005fCODE_005fSTRING-1666"></a><a name="index-gdb_002eTYPE_005fCODE_005fSTRING-1667"></a><br><dt><code>TYPE_CODE_STRING</code><dd>A string type. Note that this is only used for certain languages with |
| language-defined string types; C strings are not represented this way. |
| |
| <p><a name="index-TYPE_005fCODE_005fBITSTRING-1668"></a><a name="index-gdb_002eTYPE_005fCODE_005fBITSTRING-1669"></a><br><dt><code>TYPE_CODE_BITSTRING</code><dd>A string of bits. |
| |
| <p><a name="index-TYPE_005fCODE_005fERROR-1670"></a><a name="index-gdb_002eTYPE_005fCODE_005fERROR-1671"></a><br><dt><code>TYPE_CODE_ERROR</code><dd>An unknown or erroneous type. |
| |
| <p><a name="index-TYPE_005fCODE_005fMETHOD-1672"></a><a name="index-gdb_002eTYPE_005fCODE_005fMETHOD-1673"></a><br><dt><code>TYPE_CODE_METHOD</code><dd>A method type, as found in C<tt>++</tt> or Java. |
| |
| <p><a name="index-TYPE_005fCODE_005fMETHODPTR-1674"></a><a name="index-gdb_002eTYPE_005fCODE_005fMETHODPTR-1675"></a><br><dt><code>TYPE_CODE_METHODPTR</code><dd>A pointer-to-member-function. |
| |
| <p><a name="index-TYPE_005fCODE_005fMEMBERPTR-1676"></a><a name="index-gdb_002eTYPE_005fCODE_005fMEMBERPTR-1677"></a><br><dt><code>TYPE_CODE_MEMBERPTR</code><dd>A pointer-to-member. |
| |
| <p><a name="index-TYPE_005fCODE_005fREF-1678"></a><a name="index-gdb_002eTYPE_005fCODE_005fREF-1679"></a><br><dt><code>TYPE_CODE_REF</code><dd>A reference type. |
| |
| <p><a name="index-TYPE_005fCODE_005fCHAR-1680"></a><a name="index-gdb_002eTYPE_005fCODE_005fCHAR-1681"></a><br><dt><code>TYPE_CODE_CHAR</code><dd>A character type. |
| |
| <p><a name="index-TYPE_005fCODE_005fBOOL-1682"></a><a name="index-gdb_002eTYPE_005fCODE_005fBOOL-1683"></a><br><dt><code>TYPE_CODE_BOOL</code><dd>A boolean type. |
| |
| <p><a name="index-TYPE_005fCODE_005fCOMPLEX-1684"></a><a name="index-gdb_002eTYPE_005fCODE_005fCOMPLEX-1685"></a><br><dt><code>TYPE_CODE_COMPLEX</code><dd>A complex float type. |
| |
| <p><a name="index-TYPE_005fCODE_005fTYPEDEF-1686"></a><a name="index-gdb_002eTYPE_005fCODE_005fTYPEDEF-1687"></a><br><dt><code>TYPE_CODE_TYPEDEF</code><dd>A typedef to some other type. |
| |
| <p><a name="index-TYPE_005fCODE_005fNAMESPACE-1688"></a><a name="index-gdb_002eTYPE_005fCODE_005fNAMESPACE-1689"></a><br><dt><code>TYPE_CODE_NAMESPACE</code><dd>A C<tt>++</tt> namespace. |
| |
| <p><a name="index-TYPE_005fCODE_005fDECFLOAT-1690"></a><a name="index-gdb_002eTYPE_005fCODE_005fDECFLOAT-1691"></a><br><dt><code>TYPE_CODE_DECFLOAT</code><dd>A decimal floating point type. |
| |
| <p><a name="index-TYPE_005fCODE_005fINTERNAL_005fFUNCTION-1692"></a><a name="index-gdb_002eTYPE_005fCODE_005fINTERNAL_005fFUNCTION-1693"></a><br><dt><code>TYPE_CODE_INTERNAL_FUNCTION</code><dd>A function internal to <span class="sc">gdb</span>. This is the type used to represent |
| convenience functions. |
| </dl> |
| |
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