GParamSpec Metadata for parameter specifications #GParamSpec is an object structure that encapsulates the metadata required to specify parameters, such as e.g. #GObject properties. Parameter names need to start with a letter (a-z or A-Z). Subsequent characters can be letters, numbers or a '-'. All other characters are replaced by a '-' during construction. The result of this replacement is called the canonical name of the parameter. g_object_class_install_property(), g_object_set(), g_object_get(), g_object_set_property(), g_object_get_property(), g_value_register_transform_func() Returns whether @type "is a" %G_TYPE_PARAM. @type: a #GType ID Casts a derived #GParamSpec object (e.g. of type #GParamSpecInt) into a #GParamSpec object. @pspec: a valid #GParamSpec Checks whether @pspec "is a" valid #GParamSpec structure of type %G_TYPE_PARAM or derived. @pspec: a #GParamSpec Casts a derived #GParamSpecClass structure into a #GParamSpecClass structure. @pclass: a valid #GParamSpecClass Checks whether @pclass "is a" valid #GParamSpecClass structure of type %G_TYPE_PARAM or derived. @pclass: a #GParamSpecClass Retrieves the #GParamSpecClass of a #GParamSpec. @pspec: a valid #GParamSpec Retrieves the #GType of this @pspec. @pspec: a valid #GParamSpec Retrieves the #GType name of this @pspec. @pspec: a valid #GParamSpec Retrieves the #GType to initialize a #GValue for this parameter. @pspec: a valid #GParamSpec All fields of the GParamSpec struct are private and should not be used directly, except for the following: @g_type_instance: private #GTypeInstance portion @name: name of this parameter @flags: #GParamFlags flags for this parameter @value_type: the #GValue type for this parameter @owner_type: #GType type that uses (introduces) this paremeter The class structure for the GParamSpec type. Normally, GParamSpec classes are filled by g_param_type_register_static(). @g_type_class: the parent class @value_type: the #GValue type for this parameter @finalize: The instance finalization function (optional), should chain up to the finalize method of the parent class. @value_set_default: Resets a @value to the default value for this type (recommended, the default is g_value_reset()), see g_param_value_set_default(). @value_validate: Ensures that the contents of @value comply with the specifications set out by this type (optional), see g_param_value_set_validate(). @values_cmp: Compares @value1 with @value2 according to this type (recommended, the default is memcmp()), see g_param_values_cmp(). Through the #GParamFlags flag values, certain aspects of parameters can be configured. @G_PARAM_READABLE: the parameter is readable @G_PARAM_WRITABLE: the parameter is writable @G_PARAM_CONSTRUCT: the parameter will be set upon object construction @G_PARAM_CONSTRUCT_ONLY: the parameter will only be set upon object construction @G_PARAM_LAX_VALIDATION: upon parameter conversion (see g_param_value_convert()) strict validation is not required @G_PARAM_STATIC_NAME: the string used as name when constructing the parameter is guaranteed to remain valid and unmodified for the lifetime of the parameter. Since 2.8 @G_PARAM_STATIC_BLURB: the string used as blurb when constructing the parameter is guaranteed to remain valid and unmodified for the lifetime of the parameter. Since 2.8 #GParamFlags value alias for %G_PARAM_READABLE | %G_PARAM_WRITABLE. #GParamFlags value alias for %G_PARAM_STATIC_NAME | %G_PARAM_STATIC_NICK | %G_PARAM_STATIC_BLURB. Since 2.13.0 Mask containing the bits of #GParamSpec.flags which are reserved for GLib. Minimum shift count to be used for user defined flags, to be stored in #GParamSpec.flags. Increments the reference count of @pspec. @pspec: a valid #GParamSpec @Returns: the #GParamSpec that was passed into this function Decrements the reference count of a @pspec. @pspec: a valid #GParamSpec The initial reference count of a newly created #GParamSpec is 1, even though no one has explicitly called g_param_spec_ref() on it yet. So the initial reference count is flagged as "floating", until someone calls g_param_spec_ref (pspec); g_param_spec_sink (pspec); in sequence on it, taking over the initial reference count (thus ending up with a @pspec that has a reference count of 1 still, but is not flagged "floating" anymore). @pspec: a valid #GParamSpec Convenience function to ref and sink a #GParamSpec. @pspec: a valid #GParamSpec @Returns: the #GParamSpec that was passed into this function @Since: 2.10 Sets @value to its default value as specified in @pspec. @pspec: a valid #GParamSpec @value: a #GValue of correct type for @pspec Checks whether @value contains the default value as specified in @pspec. @pspec: a valid #GParamSpec @value: a #GValue of correct type for @pspec @Returns: whether @value contains the canonical default for this @pspec Ensures that the contents of @value comply with the specifications set out by @pspec. For example, a #GParamSpecInt might require that integers stored in @value may not be smaller than -42 and not be greater than +42. If @value contains an integer outside of this range, it is modified accordingly, so the resulting value will fit into the range -42 .. +42. @pspec: a valid #GParamSpec @value: a #GValue of correct type for @pspec @Returns: whether modifying @value was necessary to ensure validity Transforms @src_value into @dest_value if possible, and then validates @dest_value, in order for it to conform to @pspec. If @strict_validation is %TRUE this function will only succeed if the transformed @dest_value complied to @pspec without modifications. See also g_value_type_transformable(), g_value_transform() and g_param_value_validate(). @pspec: a valid #GParamSpec @src_value: souce #GValue @dest_value: destination #GValue of correct type for @pspec @strict_validation: %TRUE requires @dest_value to conform to @pspec without modifications @Returns: %TRUE if transformation and validation were successful, %FALSE otherwise and @dest_value is left untouched. Compares @value1 with @value2 according to @pspec, and return -1, 0 or +1, if @value1 is found to be less than, equal to or greater than @value2, respectively. @pspec: a valid #GParamSpec @value1: a #GValue of correct type for @pspec @value2: a #GValue of correct type for @pspec @Returns: -1, 0 or +1, for a less than, equal to or greater than result Returns the name of a #GParamSpec. @pspec: a valid #GParamSpec @Returns: the name of @pspec. Returns the nickname of a #GParamSpec. @pspec: a valid #GParamSpec @Returns: the nickname of @pspec. Returns the short description of a #GParamSpec. @pspec: a valid #GParamSpec @Returns: the short description of @pspec. Gets back user data pointers stored via g_param_spec_set_qdata(). @pspec: a valid #GParamSpec @quark: a #GQuark, naming the user data pointer @Returns: the user data pointer set, or %NULL Sets an opaque, named pointer on a #GParamSpec. The name is specified through a #GQuark (retrieved e.g. via g_quark_from_static_string()), and the pointer can be gotten back from the @pspec with g_param_spec_get_qdata(). Setting a previously set user data pointer, overrides (frees) the old pointer set, using %NULL as pointer essentially removes the data stored. @pspec: the #GParamSpec to set store a user data pointer @quark: a #GQuark, naming the user data pointer @data: an opaque user data pointer This function works like g_param_spec_set_qdata(), but in addition, a void (*destroy) (gpointer) function may be specified which is called with @data as argument when the @pspec is finalized, or the data is being overwritten by a call to g_param_spec_set_qdata() with the same @quark. @pspec: the #GParamSpec to set store a user data pointer @quark: a #GQuark, naming the user data pointer @data: an opaque user data pointer @destroy: function to invoke with @data as argument, when @data needs to be freed Gets back user data pointers stored via g_param_spec_set_qdata() and removes the @data from @pspec without invoking it's destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier. @pspec: the #GParamSpec to get a stored user data pointer from @quark: a #GQuark, naming the user data pointer @Returns: the user data pointer set, or %NULL If the paramspec redirects operations to another paramspec, returns that paramspec. Redirect is used typically for providing a new implementation of a property in a derived type while preserving all the properties from the parent type. Redirection is established by creating a property of type #GParamSpecOverride. See g_object_class_override_property() for an example of the use of this capability. @pspec: a #GParamSpec @Returns: paramspec to which requests on this paramspec should be redirected, or %NULL if none. @Since: 2.4 Creates a new #GParamSpec instance. A property name consists of segments consisting of ASCII letters and digits, separated by either the '-' or '_' character. The first character of a property name must be a letter. Names which violate these rules lead to undefined behaviour. When creating and looking up a #GParamSpec, either separator can be used, but they cannot be mixed. Using '-' is considerably more efficient and in fact required when using property names as detail strings for signals. @param_type: the #GType for the property; must be derived from #G_TYPE_PARAM @name: the canonical name of the property @nick: the nickname of the property @blurb: a short description of the property @flags: a combination of #GParamFlags @Returns: a newly allocated #GParamSpec instance This structure is used to provide the type system with the information required to initialize and destruct (finalize) a parameter's class and instances thereof. The initialized structure is passed to the g_param_type_register_static() The type system will perform a deep copy of this structure, so it's memory does not need to be persistent across invocation of g_param_type_register_static(). @instance_size: Size of the instance (object) structure. @n_preallocs: Prior to GLib 2.10, it specified the number of pre-allocated (cached) instances to reserve memory for (0 indicates no caching). Since GLib 2.10, it is ignored, since instances are allocated with the slice allocator now. @instance_init: Location of the instance initialization function (optional). @value_type: The #GType of values conforming to this #GParamSpec @finalize: The instance finalization function (optional). @value_set_default: Resets a @value to the default value for @pspec (recommended, the default is g_value_reset()), see g_param_value_set_default(). @value_validate: Ensures that the contents of @value comply with the specifications set out by @pspec (optional), see g_param_value_set_validate(). @values_cmp: Compares @value1 with @value2 according to @pspec (recommended, the default is memcmp()), see g_param_values_cmp(). Registers @name as the name of a new static type derived from #G_TYPE_PARAM. The type system uses the information contained in the #GParamSpecTypeInfo structure pointed to by @info to manage the #GParamSpec type and its instances. @name: 0-terminated string used as the name of the new #GParamSpec type. @pspec_info: The #GParamSpecTypeInfo for this #GParamSpec type. @Returns: The new type identifier. A #GParamSpecPool maintains a collection of #GParamSpecs which can be quickly accessed by owner and name. The implementation of the #GObject property system uses such a pool to store the #GParamSpecs of the properties all object types. Creates a new #GParamSpecPool. If @type_prefixing is %TRUE, lookups in the newly created pool will allow to specify the owner as a colon-separated prefix of the property name, like "GtkContainer:border-width". This feature is deprecated, so you should always set @type_prefixing to %FALSE. @type_prefixing: Whether the pool will support type-prefixed property names. @Returns: a newly allocated #GParamSpecPool. Inserts a #GParamSpec in the pool. @pool: a #GParamSpecPool. @pspec: the #GParamSpec to insert @owner_type: a #GType identifying the owner of @pspec Removes a #GParamSpec from the pool. @pool: a #GParamSpecPool @pspec: the #GParamSpec to remove Looks up a #GParamSpec in the pool. @pool: a #GParamSpecPool @param_name: the name to look for @owner_type: the owner to look for @walk_ancestors: If %TRUE, also try to find a #GParamSpec with @param_name owned by an ancestor of @owner_type. @Returns: The found #GParamSpec, or %NULL if no matching #GParamSpec was found. Gets an array of all #GParamSpecs owned by @owner_type in the pool. @pool: a #GParamSpecPool @owner_type: the owner to look for @n_pspecs_p: return location for the length of the returned array @Returns: a newly allocated array containing pointers to all #GParamSpecs owned by @owner_type in the pool Gets an #GList of all #GParamSpecs owned by @owner_type in the pool. @pool: a #GParamSpecPool @owner_type: the owner to look for @Returns: a #GList of all #GParamSpecs owned by @owner_type in the pool#GParamSpecs.