The Preferences Dialog - Using the GNAT Programming Studio

Next: GPS Themes, Up: Customizing and Extending GPS

16.1 The Preferences Dialog

This dialog, available through the menu Edit->Preferences, allows you to modify the global preferences of GPS. To enable the new preferences, you simply need to confirm by pressing the OK button. To test your changes, you can use the Apply button. Pressing the Cancel button will undo all your changes.

Each preference is composed of a label displaying the name of the preference, and an editing area to modify its value. If you leave to mouse over the label, a tool tip will be displayed giving an on-line help on the preference.

The preferences dialog is composed of several areas, accessible through the tabs at the left of the dialog. Each page corresponds to a set of preferences.

Themes
This page allows you to quickly change the current settings for GPS, including preferences, key bindings, menus.... See GPS Themes for more information on themes. It is only displayed when there are themes registered.
General

Default font
The default font used in GPS
Fixed view font
The fixed (monospace) font used in views like the outline view, the bookmark view,.... As much as possible, this font should use a fixed width for characters, for a better rendering
Character set
Name of character set to use when reading or writting text files. GPS uses UTF-8 and Unicode internally, which can handle any character in any language. However, your system will generally not support Unicode natively, and thus the contents of the files should be translated from the file system encoding to unicode.
This preference indicates the file system encoding in use. It defaults to ISO-8859-1, which corresponds to western european characters.
Dynamic key bindings
Whether the menu key bindings can be changed interactively.
When this preference is enabled, you can navigate through the menus, and type the key binding you want to associate to a particular item. To remove a key binding, use the <Backspace> key.
Display splash screen
Whether a splash screen should be displayed when starting GPS.
Display welcome window
Whether GPS should display the welcome window for the selection of the project to use.
Tool bar style
How the tool bar should be displayed: not at all, with small icons or with large icons
Show status bar
Whether the status bar at the bottom of the GPS window should be displayed. This status bar contains one or more progress bars while GPS is executing long actions like a build or a search. These progress bars can be used to monitor the progress of those actions.
If you wish to save vertical screen space, you can hide this status bar. The progress bars will no longer be visible. Instead, you can display the Task Manager through the Tools->Views->Tasks menu, to get similar information. This manager can then be put on the right or left side of the GPS window, for instance just below the Project View.
Show text in tool bar
Whether the tool bar should show both text and icons, or only icons.
Auto save
Whether unsaved files and projects should be saved automatically before calling external tools (e.g. before a build).
Save project-specific desktop on exit
Whether the desktop (size and positions of all windows) should be saved when exiting. The default desktop is never saved automatically, i.e. GPS will only save a desktop associated with the current project. If you are working with a project created automatically by GPS, the desktop will not be saved.
Save editor in desktop
Determines when source editors should be saved in the desktop: Never, Always, or when a source file is associated with the current project (From_Project).
Clipboard size
This controls the size of the list where all the entries copied into the clipboard through Edit->Copy and Edit->Cut are saved. This list is navigated through the menu Edit->Paste and Edit->Paste Previous, as described earlier in this guide.
Multi language build
Whether GPS should build (using gprmake) more than just Ada sources for projects containing Ada and other (e.g. C) languages.
By default, GPS will call gnatmake to build projects containing Ada sources, meaning that non Ada sources won't be built. By enabling this preference, a multi-language build tool, called gprmake will be called. Note that this tool is still under development, so this option should only be activated with caution.
Jump to first location
Whether the first entry of the location window should be selected automatically, and thus whether the corresponding editor should be immediately open.
Windows
This section specifies preferences that apply to the Multiple Document Interface described in Multiple Document Interface.

Opaque
If True, items will be resized or moved opaquely when not maximized.
Destroy floats
If False, closing the window associated with a floating item will put the item back in the main GPS window, but will not destroy it. If True, the item is destroyed.
All floating
If True, then all the windows will be floating by default, i.e. be under the control of your system (Windows) or your window manager (Unix machines). This replaces the MDI.
Background color
Color to use for the background of the MDI.
Title bar color
Color to use for the title bar of unselected items.
Selected title bar color
Color to use for the title bar of selected items.
Show title bars
If True, each window in GPS will have its own title bars, showing some particular information (like the name of the file edited for editors), and some buttons to iconify, maximize or close the window. This title bar is highlighted when the window is the one currently selected.
If False, the title bar is not displayed, to save space on the screen. The tabs of the notebooks will then be highlighted.
Notebook tabs policy
Indicates when the notebook tabs should be displayed. If set to "Never", you will have to select the window in the Window menu, or through the keyboard. If set to "Automatic", then the tabs will be shown when two or more windows are stacked.
Notebook tabs position
Indicates where the notebook tabs should be displayed
Editor
General
Strip blanks
Whether the editor should remove trailing blanks when saving a file.
Line terminator
Choose between Unix, Windows and Unchanged line terminators when saving files. Choosing Unchanged will use the original line terminator when saving the file; Unix will use LF line terminators; Windows will use CRLF line terminators.
Display line numbers
Whether the line numbers should be displayed in file editors.
Display subprogram names
Whether the subprogram name should be displayed in the editor's status bar.
Tooltips
Whether tool tips should be displayed automatically.
Tooltips timeout
Time (in milliseconds) before displaying tooltips.
Highlight delimiters
Determine whether the delimiter matching the character following the cursor should be highlighted. The list of delimiters includes: {}[]()
Autosave delay
The period (in seconds) after which an editor is automatically saved, 0 if none.
Each modified file is saved under a file called .#filename#, which is removed on the next explicit save operation.
Right margin
The right margin to highlight. 0 if none. This value is also used to implement the Edit->Refill command.
Block highlighting
Whether the editor should highlight the current block. The current block depends on the programming language, and will include e.g. procedures, loops, if statements, ...
Block folding
Whether the editor should provide the ability to fold/unfold blocks.
Speed Column Policy
When the Speed Column should be shown on the side of the editors:

Never
The Speed Column is never displayed.
Automatic
The Speed Column is shown whenever lines are highlighted in the editor, for example to show the current execution point, or lines containing compilation errors, ... It disappears when no lines are highlighted.
Always
The Speed Column is always displayed.

External editor
The default external editor to use.
Custom editor command
Specify the command line for launching a custom editor. It is assumed that the command will create a new window/terminal as needed. If the editor itself does not provide this capability (such as vi or pico under Unix systems), you can use an external terminal command, e.g:
xterm -geo 80x50 -exe vi +%l %f

The following substitutions are provided:

%l
line to display
%c
column to display
%f
full pathname of file to edit
%e
extended lisp inline command
%p
top level project file name
%%
percent sign ('%')
Always use external editor
True if all editions should be done with the external editor. This will deactivate completely the internal editor. False if the external editor needs to be explicitly called by the user.
Fonts & Colors

Default
The default font, default foreground and default background colors used in the source editor.
Keywords
Font and colors used to highlight keywords.
Comments
Font and colors used to highlight comments. Setting the color to white will set a transparent color.
Strings
Font and colors used to highlight strings. Setting the color to white will set a transparent color.
Current line color
Color for highlighting the current line. Leave it to blank for no highlighting. Setting the color to white will set a transparent color.
Current block color
Color for highlighting the current source block.
Delimiter highlighting color
Color for highlighting delimiters.
Search results highlighting
Color for highlighting the search results in the text of source editors.
Cursor color
Color used for the cursor in editors and interactive consoles
Cursor aspect ratio
Defines the size of the cursor, relatively to characters. 100 means the cursor will occupy the same size as a character, 10 means it will only occupy 10% of the size occupies by a character.

Ada
Auto indentation
How the editor should indent Ada sources. None means no indentation; Simple means that indentation from the previous line is used for the next line; Extended means that a language specific parser is used for indenting sources.
Use tabulations
Whether the editor should use tabulations when indenting.
Default indentation
The number of spaces for the default Ada indentation.
Continuation lines
The number of extra spaces for continuation lines.
Declaration lines
The number of extra spaces for multiple line declarations. For example, using a value of 4, here is how the following code would be indented:

variable1, variable2, variable3 : Integer;
Conditional continuation lines
The number of extra spaces used to indent multiple lines conditionals within parentheses.
For example, when this preference is set to 1 (the default), continuation lines are indented based on the previous parenthesis plus one space:

if (Condition1 and then Condition2) then

When this preference is set to 3, this gives:

if (Condition1 and then Condition2) then
Record indentation
The number of extra spaces for record definitions, when the record keyword is on its own line.
For example, when this preference is set to 3 (the default), the following sample will be indented as:

type T is record F : Integer; end record;

When this preference is set to 1, this gives:

type T is record F : Integer; end record;
Case indentation
Whether GPS should indent case statements with an extra level, as used in the Ada Reference Manual, e.g:

case Value is when others => null; end case;

If this preference is set to Non_Rm_Style, this would be indented as:

case Value is when others => null; end case;

By default (Automatic), GPS will choose to indent with an extra level or not based on the first when construct: if the first when is indented by an extra level, the whole case statement will be indented following the RM style.
Casing policy
The way the editor will handle the case settings below. Disabled no auto-casing will be done; End_Of_Line auto-casing will be done when hitting <Enter> key; On_The_Fly auto-casing will be done word-by-word while typing. For the End_Of_Line and On_The_Fly policies it is always possible to force the casing of the current line by pressing the indentation key (<Ctrl-Tab> by default).
Reserved word casing
How the editor should handle reserved words casing. Unchanged will keep the casing as-is; Upper will change the casing of all reserved words to upper case; Lower will change the casing to lower case; Mixed will change the casing to mixed case (all characters to lower case except first character and characters after an underscore which are set to upper case); Smart_Mixed As above but do not force upper case characters to lower case.
Identifier casing
How the editor should handle identifiers casing. The values are the same as for the Reserved word casing preference.
Format operators/delimiters
Whether the editor should add extra spaces around operators and delimiters if needed. If enabled, an extra space will be added when needed in the following cases: before an opening parenthesis; after a closing parenthesis, comma, semicolon; around all Ada operators (e.g. <=, :=, =>, ...)
Align colons in declarations
Whether the editor should automatically align colons in declarations and parameter lists. Note that the alignment is computed by taking into account the current buffer up to the current line (or end of the current selection), so if declarations continue after the current line, you can select the declarations lines and hit the reformat key.
Align associations on arrows
Whether the editor should automatically align arrows in associations (e.g. aggregates or function calls). See also previous preference.
Align declarations after colon
Whether the editor should align continuation lines in variable declarations based on the colon character.
Consider the following code:

Variable : constant String := "a string";

If this preference is enabled, it will be indented as follows:

Variable : constant String := "a string";
Indent comments
Whether to indent lines containing only comments and blanks, or to keep these lines unchanged.
Align comments on keywords
Whether to align comment lines following record and is keywords immediately with no extra space.
When enabled, the following code will be indented as:

package P is -- Comment [...] end P;

When disabled, the indentation will be:

package P is -- Comment [...] end P;
C/C++

Auto indentation
How the editor should indent C/C++ sources. None means no indentation; Simple means that indentation from the previous line is used for the next line; Extended means that a language specific parser is used for indenting sources.
Use tabulations
Whether the editor should use tabulations when indenting. If True, the editor will replace each occurrence of eight characters by a tabulation character.
Default indentation
The number of spaces for the default indentation.
Debugger

Preserve State on Exit
If this preference is enabled, the debugger will automatically save breakpoints when it exists, and restore them the next time the same executable is debugged. This is a convenient way to work on an executable, where the typical usage looks like compile, debug, compile, debug,...
When the preference is enabled, the debugger will also preserve the contents of the data window whenever it is closed. Reopening the window either during the same debugger session, or automatically when a new debugger is started on the same executable, will recreate the same boxes within the data window.
Break on exceptions
Specifies whether a breakpoint on all exceptions should be set by default when loading a program. This setup is only taken into account when a new debugger is initialized, and will not modify a running debugger (use the breakpoint editor for running debuggers).
Execution window
Specifies whether the debugger should create a separate execution window for the program being debugged.
Note that this preference cannot be taken into account for the current debug session: you need to terminate the current debug session and restart a new one.
If true, a separate console will be created. Under Unix systems, this console is another window in the bottom part of the main window; under Windows, this is a separate window created by the underlying gdb, since Windows does not have the notion of separate terminals (aka ttys).
Note that in this mode under Windows, the Debug->Interrupt menu will not interrupt the debugged program. Instead, you need to hit <Ctrl-C> in the separate execution window to interrupt it while it is running. On Windows this separate execution window uses the default system-wide console properties (the size of the window, the colors...). It is possible to change those properties using the default console menu (top-left of the console) on Windows XP or using the control panel on Windows NT.
If false, no execution window will be created. The debugger assumes that the program being debugged does not require input, or that if it does, input is handled outside GPS. For example, when you attach to a running process, this process already has a separate associated terminal.
Show lines with code
Specifies whether the source editor should display blue dots for lines that contain code. If set to False, gray dots will be displayed instead on each line, allowing breakpoint on any line. Disabling this option provides a faster feedback, since GPS does not need to query the debugger about which lines contain code.
Detect aliases
If enabled, do not create new items when an item with the same address is already present on the canvas.
Assembly range size
Number of assembly lines to display in the initial display of the assembly window. If the size is 0, then the whole subprogram is displayed, but this can take a very long time on slow machines.
Current assembly line
Color used to highlight the assembly code for the current line.
Color highlighting
Color used for highlighting in the debugger console.
Clickable item
Indicates color to be used for the items that are click-able (e.g pointers).
Changed data
Indicates color to be used to highlight fields in the data window that have changed since the last update.
Memory color
Color used by default in the memory view window.
Memory highlighting
Color used for highlighted items in the memory view.
Memory selection
Color used for selected items in the memory view.
Item name
Indicates the font to be used for the name of the item in the data window.
Item type
Indicates font to be used to display the type of the item in the data window.
External Commands

List processes
Command used to list processes running on the machine.
Remote shell
Program used to run a process on a remote machine. You can specify arguments, e.g. rsh -l user
Remote copy
Program used to copy a file from a remote machine. You can specify arguments, e.g. rcp -l user
Execute command
Program used to execute commands externally.
HTML Browser
Only used under Unix, not relevant under Windows where the default HTML browser is used. Program used to execute view HTML files, for instance the documentation. Empty by default, which means that GPS will try to find a suitable HTML browser automatically. Only change the value if GPS cannot find a HTML browser, or if the browser found is not your preferred one.
Print command
External program used to print files.
This program is required under Unix systems in order to print, and is set to a2ps by default. If a2ps is not installed on your system, you can download it from ftp://ftp.enst.fr/pub/unix/a2ps/, although other printing programs such as lp can be specified instead.
Under Windows systems, this program is optional and is empty by default, since a built-in printing is provided. An external tool will be used if specified, such as the PrintFile freeware utility available from http://www.lerup.com/printfile/descr.html
Browsers

General

Selected item color
Color to use to draw the selected item.
Background color
Color used to draw the background of the browsers.
Hyper link color
Color used to draw the hyper links in the items.
Selected link color
Color to use for links between selected items.
Default link color
Color used to draw the links between unselected items.
Ancestor items color
Color to use for the background of the items linked to the selected item.
Offspring items color
Color to use for the background of the items linked from the selected item.
Vertical layout
Whether the layout of the graph should be vertical (True) or horizontal (False).

File Dependencies

Show system files
Whether the system files (Ada runtime or standard C include files) should be visible in the browser.
Show implicit dependencies
If False, then only the explicit dependencies are shown in the browser. Otherwise, all dependencies, even implicit, are displayed.
Visual diff Note that in order to perform visual comparison between files, GPS needs to call external tool (not distributed with GPS) such as diff or patch. These tools are usually found on most unix systems, and may not be available by default on other OSes. Under Windows, you can download them from one of the unix toolsets available, such as msys (http://www.mingw.org/msys.shtml) or cygwin (http://www.cygwin.com).

Diff command
Command used to compute differences between two files. Arguments can also be specified. The visual diff expects a standard diff output with no context (that is, no -c nor -u switch). Arguments of interest may include (this will depend on the version of diff used):

-b
Ignore changes in amount of white space.
-B
Ignore changes that just insert or delete blank lines.
-i
Ignore changes in case; consider upper and lower case letters equivalent.
-w
Ignore white space when comparing lines.

Patch command
Command used to apply a patch. Arguments can also be specified. This command is used internally by GPS to perform the visual comparison on versioned files (e.g. when performing a comparison with a version control system).
This command should be compatible with the GNU patch utility.
Use old diff
Use the old version of the visual comparison.
Diff3 command
This item is only displayed if the preference Use old diff is disabled. Command used to query a 3-way diff. See Diff command for a description of the parameters.
Default color
This item is only displayed if the preference Use old diff is disabled. The color used to indicate lines on which there is a difference, in the "reference" editor.
Old color
This item is only displayed if the preference Use old diff is disabled. The color used to indicate spaces used by lines not present in one of the editors in a 3-way diff and present in the other editors.
Append color
This item is only displayed if the preference Use old diff is disabled. The color used to display the lines that are present in an editor but not in the reference editor.
Remove color
This item is only displayed if the preference Use old diff is disabled. The color used to display the lines that are present in the reference editor but not in other editors.
Change color
This item is only displayed if the preference Use old diff is disabled. The color used to display the lines that have changed between the reference editor and the other editors.
Fine change color
This item is only displayed if the preference Use old diff is disabled. The color used to highlight fine differences within a modified line.
Context length
This item is only displayed if the preference Use old diff is enabled. The number of lines displayed before and after each chunk of differences. Specifying -1 will display the whole file.
Messages

Color highlighting
Color used to highlight text in the messages window.
Color highlighting
Color used to highlight lines causing compilation errors/warnings in the source editors. When this color is set to white, the errors/warnings are not highlighted. (Compilation/Build)
File pattern
Pattern used to detect file locations and the type of the output from the messages window. This is particularly useful when using an external tool such as a compiler or a search tool, so that GPS will highlight and allow navigation through source locations. This is a standard system V regular expression containing from two to five parenthesized subexpressions corresponding to the file, line, column, warnings or style error patterns.
File index
Index of filename in the file pattern.
Line index
Index of the line number in the file pattern.
Column index
Index of the column number in the file pattern.
Warning index
Index of the warning identifier in the file pattern.
Style index
Index of the style error identifier in the file pattern.
Project
Relative project paths
Whether paths should be absolute or relative when the projects are modified.
Fast Project Loading
If the project respects a number of restrictions, activating the preference will provide major speed up when GPS parses the project. This is especially noticeable if the source files are on a network drive.
GPS assumes that the following restricitions are true when the preference is activated. If this isn't the case, no error is reported, and only minor drawacks will be visible in GPS (no detection that two files are the same if one of them is a symbolic link for instance, although GPS will still warn you if you are trying to overwrite a file modified on the disk).
The restrictions are the following:
- Symbolic links shouldn't be used in the project. More precisely, you can only have symbolic links that point to files outside of the project, but not to another file in the project
- Directories can't have source names. No directory name should match the naming scheme defined in the project. For instance, if you are using the default GNAT naming scheme, you cannot have directories with names ending with ".ads" or ".adb"
Load Xref info on project load
Whether the Xref information should be automatically loaded into memory when a new project is loaded. See Support for Cross-References.
Outline

Font
You can choose a specific font for the outline view. Typically, this will be used to use a slightly smaller font than in the editor, so that you can see more entities at once on the screen.
Show Profiles
For some of the languages, in particular Ada, GPS can display the profile (list of parameters) for the subprograms. This can be used to differentiate between overloaded entities (ie entities with the same name). Disabling this preference will only show the entity name.
Sort alphabetically
If this preference is activated, the entities will be sorted alphabetically in the outline view. If disabled, they will be displayed in the order they are found in the source file.
Link with Editor
If this option is set, the current subprogram will be selected in the outline view every time the cursor position changes in the current editor. This option requires some computation for GPS, and you might want to avoid the slow down by disabling it.
Show file name
If this option is set, the outline view will show the name of the file on its first line, and indent slightly all following lines. If this option is unset, this will save some screen real estate, but you will have to look at the current editor to see what file is descrived in the Outline View.
Documentation This section specifies preferences that apply to the Documentation Generator. Documentation Generation for more information.

Process body files
If this preference is enabled, implementation files will be processed. Otherwise, only the specification files will.
Show private entities
By default, no documentation is generated for private entities. Enabling this preference will change this behavior.
Create all links
Choosing this option will activate the creation of links to files that are not processed.
List tagged types
If enabled, an index will be created that lists all tagged types as well as their parents and childs. Links are created in order to ease the navigation.