11.7.9 Attributes

A project (and its packages) may have attributes that define the project's properties. Some attributes have values that are strings; others have values that are string lists.

     attribute_declaration ::=
        simple_attribute_declaration | indexed_attribute_declaration
     simple_attribute_declaration ::= for attribute_designator use expression ;
     indexed_attribute_declaration ::=
       for <indexed_attribute_>simple_name ( string_literal) use expression ;
     attribute_designator ::=
       <simple_attribute_>simple_name
       | <indexed_attribute_>simple_name ( string_literal )

There are two categories of attributes: simple attributes and indexed attributes. Each simple attribute has a default value: the empty string (for string attributes) and the empty list (for string list attributes). An attribute declaration defines a new value for an attribute, and overrides the previous value. The syntax of a simple attribute declaration is similar to that of an attribute definition clause in Ada.

Some attributes are indexed. These attributes are mappings whose domain is a set of strings. They are declared one association at a time, by specifying a point in the domain and the corresponding image of the attribute. Like untyped variables and simple attributes, indexed attributes may be declared several times. Each declaration supplies a new value for the attribute, and replaces the previous setting.

Here are some examples of attribute declarations:

        --  simple attributes
        for Object_Dir use "objects";
        for Source_Dirs use ("units", "test/drivers");
     
        --  indexed attributes
        for Body ("main") use "Main.ada";
        for Switches ("main.ada") use ("-v", "-gnatv");
        for Switches ("main.ada") use Builder'Switches ("main.ada") & "-g";
     
        --  indexed attributes copy (from package Builder in project Default)
        --  The package name must always be specified, even if it is the current
        --  package.
        for Default_Switches use Default.Builder'Default_Switches;

Attributes references may be appear anywhere in expressions, and are used to retrieve the value previously assigned to the attribute. If an attribute has not been set in a given package or project, its value defaults to the empty string or the empty list.

     attribute_reference ::= attribute_prefix ' <simple_attribute>_simple_name [ (string_literal) ]
     attribute_prefix ::= project
       | <project_>simple_name
       | package_identifier
       | <project_>simple_name . package_identifier

Examples are:

       project'Object_Dir
       Naming'Dot_Replacement
       Imported_Project'Source_Dirs
       Imported_Project.Naming'Casing
       Builder'Default_Switches ("Ada")

The prefix of an attribute may be:

• project for an attribute of the current project
• The name of an existing package of the current project
• The name of an imported project
• The name of a parent project that is extended by the current project
• An expanded name whose prefix is imported/parent project name, and whose selector is a package name

Legal attribute names are listed below, including the package in which they must be declared. These names are case-insensitive. The semantics for the attributes is explained in great details in other sections.

The column index indicates whether the attribute is an indexed attribute, and when it is whether its index is case sensitive (sensitive) or not (insensitive), or if case sensitivity depends is the same as file names sensitivity on the system (file). The text is between brackets ([]) if the index is optional.

Attribute Name	Value	Package	Index
General attributes			see Building With Projects
Name	string	-	(Read-only, name of project)
Project_Dir	string	-	(Read-only, directory of project)
Source_Files	list	-	-
Source_Dirs	list	-	-
Source_List_File	string	-	-
Locally_Removed_Files	list	-	-
Excluded_Source_Files	list	-	-
Object_Dir	string	-	-
Exec_Dir	string	-	-
Excluded_Source_Dirs	list	-	-
Excluded_Source_Files	list	-	-
Excluded_Source_List_File	list	-	-
Inherit_Source_Path	list	-	insensitive
Languages	list	-	-
Main	list	-	-
Main_Language	string	-	-
Externally_Built	string	-	-
Roots	list	-	file
Library-related attributes			see Library Projects
Library_Dir	string	-	-
Library_Name	string	-	-
Library_Kind	string	-	-
Library_Version	string	-	-
Library_Interface	string	-	-
Library_Auto_Init	string	-	-
Library_Options	list	-	-
Leading_Library_Options	list	-	-
Library_Src_Dir	string	-	-
Library_ALI_Dir	string	-	-
Library_GCC	string	-	-
Library_Symbol_File	string	-	-
Library_Symbol_Policy	string	-	-
Library_Reference_Symbol_File	string	-	-
Interfaces	list	-	-
Naming			see Naming Schemes
Spec_Suffix	string	Naming	insensitive (language)
Body_Suffix	string	Naming	insensitive (language)
Separate_Suffix	string	Naming	-
Casing	string	Naming	-
Dot_Replacement	string	Naming	-
Spec	string	Naming	insensitive (Ada unit)
Body	string	Naming	insensitive (Ada unit)
Specification_Exceptions	list	Naming	insensitive (language)
Implementation_Exceptions	list	Naming	insensitive (language)
Building			see Switches and Project Files
Default_Switches	list	Builder, Compiler, Binder, Linker, Cross_Reference, Finder, Pretty_Printer, gnatstub, Check, Synchronize, Eliminate, Metrics, IDE	insensitive (language name)
Switches	list	Builder, Compiler, Binder, Linker, Cross_Reference, Finder, gnatls, Pretty_Printer, gnatstub, Check, Synchronize, Eliminate, Metrics, Stack	[file] (file name)
Local_Configuration_Pragmas	string	Compiler	-
Local_Config_File	string	insensitive	-
Global_Configuration_Pragmas	list	Builder	-
Global_Compilation_Switches	list	Builder	language
Executable	string	Builder	[file]
Executable_Suffix	string	Builder	-
Global_Config_File	string	Builder	insensitive (language)
IDE (used and created by GPS)
Remote_Host	string	IDE	-
Program_Host	string	IDE	-
Communication_Protocol	string	IDE	-
Compiler_Command	string	IDE	insensitive (language)
Debugger_Command	string	IDE	-
Gnatlist	string	IDE	-
VCS_Kind	string	IDE	-
VCS_File_Check	string	IDE	-
VCS_Log_Check	string	IDE	-
Documentation_Dir	string	IDE	-
Configuration files			See gprbuild manual
Default_Language	string	-	-
Run_Path_Option	list	-	-
Run_Path_Origin	string	-	-
Separate_Run_Path_Options	string	-	-
Toolchain_Version	string	-	insensitive
Toolchain_Description	string	-	insensitive
Object_Generated	string	-	insensitive
Objects_Linked	string	-	insensitive
Target	string	-	-
Library_Builder	string	-	-
Library_Support	string	-	-
Archive_Builder	list	-	-
Archive_Builder_Append_Option	list	-	-
Archive_Indexer	list	-	-
Archive_Suffix	string	-	-
Library_Partial_Linker	list	-	-
Shared_Library_Prefix	string	-	-
Shared_Library_Suffix	string	-	-
Symbolic_Link_Supported	string	-	-
Library_Major_Minor_Id_Supported	string	-	-
Library_Auto_Init_Supported	string	-	-
Shared_Library_Minimum_Switches	list	-	-
Library_Version_Switches	list	-	-
Library_Install_Name_Option	string	-	-
Runtime_Library_Dir	string	-	insensitive
Runtime_Source_Dir	string	-	insensitive
Driver	string	Compiler,Binder,Linker	insensitive (language)
Required_Switches	list	Compiler,Binder,Linker	insensitive (language)
Leading_Required_Switches	list	Compiler	insensitive (language)
Trailing_Required_Switches	list	Compiler	insensitive (language)
Pic_Options	list	Compiler	insensitive (language)
Path_Syntax	string	Compiler	insensitive (language)
Object_File_Suffix	string	Compiler	insensitive (language)
Object_File_Switches	list	Compiler	insensitive (language)
Multi_Unit_Switches	list	Compiler	insensitive (language)
Multi_Unit_Object_Separator	string	Compiler	insensitive (language)
Mapping_File_Switches	list	Compiler	insensitive (language)
Mapping_Spec_Suffix	string	Compiler	insensitive (language)
Mapping_body_Suffix	string	Compiler	insensitive (language)
Config_File_Switches	list	Compiler	insensitive (language)
Config_Body_File_Name	string	Compiler	insensitive (language)
Config_Body_File_Name_Index	string	Compiler	insensitive (language)
Config_Body_File_Name_Pattern	string	Compiler	insensitive (language)
Config_Spec_File_Name	string	Compiler	insensitive (language)
Config_Spec_File_Name_Index	string	Compiler	insensitive (language)
Config_Spec_File_Name_Pattern	string	Compiler	insensitive (language)
Config_File_Unique	string	Compiler	insensitive (language)
Dependency_Switches	list	Compiler	insensitive (language)
Dependency_Driver	list	Compiler	insensitive (language)
Include_Switches	list	Compiler	insensitive (language)
Include_Path	string	Compiler	insensitive (language)
Include_Path_File	string	Compiler	insensitive (language)
Prefix	string	Binder	insensitive (language)
Objects_Path	string	Binder	insensitive (language)
Objects_Path_File	string	Binder	insensitive (language)
Linker_Options	list	Linker	-
Leading_Switches	list	Linker	-
Map_File_Options	string	Linker	-
Executable_Switches	list	Linker	-
Lib_Dir_Switch	string	Linker	-
Lib_Name_Switch	string	Linker	-
Max_Command_Line_Length	string	Linker	-
Response_File_Format	string	Linker	-
Response_File_Switches	list	Linker	-