Plug-in Installation

Prerequisites

Eclipse

Before installing the EPIC plug-in Eclipse version 3.0 or higher has to be installed.
Eclipse comes in two flavors. The SDK version contains Java IDE components and is much larger than the Platform version. If you only want to use Eclipse as Perl IDE the Platform version is sufficient. If you are in for Perl and Java coding, use the SDK version.

Eclipse can be downloaded from www.eclipse.org.

Perl

In order to have all EPIC features like Syntax Checking, Source Formatting etc. a perl interpreter is needed. In principle any Perl interpreter can be used. To use debugging within eclipse Perl version 5.8.x or 5.6.x  is required. For further requirements concerning the debugger see  Setting up the Debugger .
Most *nix/Linux installations will provide Perl interpreters out of the box.
For Window, Perl can be downloaded from www.activestate.com.

Installation

The installation is done by using the Eclipse Update Manager. The Update Manager connects to an EPIC Update Site [http://e-p-i-c.sourceforge.net/updates]. The Update Site can also be stored locally if no Internet connection is available and can be downloaded form the EPIC project page.

After starting Eclipse, select Help > Software and Updates > Find and Install... from the menu.

Find and Install...


Select Search for new features to install an press Next.

Press the Add Update Site... button for a remote installation via HTTP or the Add Local Site... button if the Update Site is available locally.
When installing EPIC from remote enter any desired Name and the URL http://e-p-i-c.sf.net/updates.

Add Update Site...


Tick the newly created site and press the Next button.
Follow the instructions of the install wizard. The warning about the installation of an unsigned feature can be ignored.
After installation Eclipse has to be restarted.

Now the EPIC installation should be complete.

Setting up Preferences

EPIC preferences can be accessed via Window > Preferences... from the Eclipse Menu.

Preferences...

General Preferences

Click on Perl EPIC to open the General Preferences page.
General preferences include the location of the Perl interpreter, the option to enable warnings, taint mode and the interval of the source validation.
The validation interval indicated when to start validation after the editor is idle.
Apart from the standard interpreter type, the type can be switched to Cygwin. In this case the @INC path is mapped to be Cygwin compliant.

Code Assist

On the Code Assist Preference Page the auto completion trigger characters are defined. Normally it should not be necessary these values.
By default the editor suggests a list of already used variables when the characters $ @ % are typed. To switch this feature off, deselect the Inspect Variables check box.

Code Assist Preferences

Editor

These options define the appearance of the Perl Editor , the coloring of the Perl source code and how annotations are displayed.

Editor Preferences

Source Formatter

EPIC uses PerlTidy to format source code. The Source Formatter Preference allows to specify PerlTidy command line parameters. To get a description of available parameters, press the Help key and select PerlTidy options from the popup menu.

Source Formatter Preferences

NOTE: In order for PerlTidy to work correctly the Perl Interpreter Preferences have to be setup correctly (see above).

Templates

Templates are a powerful tool to insert pre defined code snippets while working with the  Perl Editor.

Template Preferences

How Templates are use is covered in Working with the Perl Editor. The Templates Preference page allows the creation, import and export of Templates.
On export Templates are stored in XML format.


Associating Files with the Perl editor

Eclipse file extension are associated with an editor. If another plug-in is installed the EPIC Perl Editor might not be used as standard editor when opening *.pl, *.pm or *.cgi files.
To associate these file extensions with the Perl Editor choose Window > Preferences from the Eclipse menu and select Workbench > File Associations.

If the Perl extensions are missing they can be created by pressing the Add... button.
Select the Perl Editor from the list and press the Default button.

File Associations


CVS Setup

On default Eclipse stores Perl files as binary when they are added to the CVS repository.
To store Perl files as text (ASCII) select Window > Preferences... from the Eclipse menu and modify the Team > File Content settings.
Add your Perl extensions (pl, pm etc.) by pressing the Add... button and specify ASCII in the Contents column.

CVS File Content


Setting up the Debugger

Setting up the debugger requires two steps:
  1. Define the Perl interpreter to use
  2. Install the PadWalker Perl module
    NOTE: It is possible to use the debugger without installing PadWalker. But in this case local variables won't be shown.
    Download the PadWalker module from CPAN  (PadWalker 0.10) and install as described in the installation notes or use the installation manager provided with your Perl installation (e.g. PPM for ActiveState installations).
    If you are using ActiveState 5.8.x on Windows system you can download a pre-compiled PadWalker module from the EPIC homepage as the version provided by ActiveState doesn't seem to work for Perl 5.8.x (but it does for 5.6.x).


Perl Projects

Creating a Project

Perl projects are created (like any other Project) by selecting File > New > Project... from the Eclipse menu.

Creating a Project

After following the instructions of the wizard the Perl Project will be created. In the Navigator the Perl folder icon Project Icon is assigned to Perl Projects.

Perl Include Path

To expand the Perl Include Path (@INC) right click on the project icon and select Properties...

@INC Path Settings

Converting an existing Project

To add the Perl Nature to an existing Project, select the Project in the Navigator and select Add Perl Nature from the dropdown menu.

Change Perl Nature

To remove a Perl Nature form a project, select a Perl project and select Remove Perl Nature form the popup menu.

Eclipse Basics

Perspectives

Each Workbench window contains one or more perspectives. A perspective defines the initial set and layout of views in the Workbench window. Within the window, each perspective shares the same set of editors. Each perspective provides a set of capabilities aimed at accomplishing a specific type of task or works with specific types of resources. For example, the Java perspective combines views that you would commonly use while editing Java source files, while the Debug perspective contains the views that you would use while debugging Java programs. As you work in the Workbench, you will probably switch perspectives frequently.

Perspectives control what appears in certain menus and toolbars. They define visible action sets, which you can change to customize a perspective. You can save a perspective that you build in this manner, making your own custom perspective that you can open again later.  

You can set your Workbench preferences to open perspectives in the same window or in a new window.

The main perspectives perspectives for developing Perl applications are
: This is the main view for coding  Perl scripts
: Provides the main functionally for debugging and executing Perl scripts. For details see Debug Perspective .

Views

Views support editors and provide alternative presentations as well as ways to navigate the information in your Workbench.  For example, the Navigator view displays projects and other resources that you are working with.

Views also have their own menus. To open the menu for a view, click the icon at the left end of the view's title bar. Some views also have their own toolbars. The actions represented by buttons on view toolbars only affect the items within that view. 

A view might appear by itself, or stacked with other views in a tabbed notebook. You can change the layout of a perspective by opening and closing views and by docking them in different positions in the Workbench window.


Using Perspectives

New perspectives

There are several ways to open a new perspective within this Workbench window:

  • Using the Open Perspective button Open Perspectives on the shortcut bar.
  • Choosing a perspective from the Window > Open Perspective menu. 

To open one by using the shortcut bar button:

  1. Click on the Open Perspective button Open Perspectives

  2. A menu appears showing the same choices as shown on the Window > Open Perspective menu. Choose Other from the menu.

    Open Perspective Menu

  3. In the Select Perspective dialog choose Debug and click OK

    Select Perspective

    The Debug perspective is displayed.  

  4. There are several other interesting things to take note of. 

    • The title of the window now indicates that the Debug perspective is in use. 

    • The shortcut bar contains several perspectives, the original Resource perspective, the new Debug perspective and a few others. The Debug perspective button is pressed in, indicating that it is the current perspective.

    • To disply the full name of the perspective right click the perspective bar and check Show Text.
      Debug Perspective

  5. In the shortcut bar, click on the Resource perspective button. The Resource perspective is once again the current perspective. Notice that the set of views is different for each of the perspectives.

Configuring perspectives

In addition to configuring the layout of a perspective you can also control several other key aspects of a perspective. These include:
  • The New menu.
  • The Window > Open Perspective menu.
  • The Window > Show View menu.
  • Action sets that show up on the toolbar.

Try customizing one of these items. 

  1. In the shortcut bar click on the Resource perspective. 

  2. Select Window > Customize Perspective...

  3. Select the Commands tab. 

  4. Check Launch and click OK.

    Customizing Perspective

  5. Observe that the toolbar now includes buttons for debug/run launching.

    Customized Perspective

  6. After experimenting with the other options on the Customize Perspective dialog, choose Window > Reset Perspective to return the perspective to its original state. 

Saving a user defined perspective

If you have modified a perspective by adding, deleting, or moving (docking) views, you can save your changes for future use.

  1. Switch to the perspective that you want to save.
  2. Click Window > Save Perspective As.
  3. Type a new name for the perspective into the Name field.
  4. Click OK.

Resetting perspectives

To restore a perspective to its original layout:

  1. Click Window > Preferences.
  2. Expand Workbench and choose Perspectives.
  3. From the Available perspectives list, select the perspective you want to restore.
  4. Click Reset.
  5. Click OK.

Using views

Opening views

Perspectives offer pre-defined combinations of views and editors. To open a view that is not included in the current perspective, select Window > Show View from the main menu bar.

You can create fast views to provide a shortcut to views that you use often.

After adding a view to the current perspective, you may wish to save your new layout by clicking Window > Save Perspective As.

Moving and docking views

To change the location of a view in the current perspective:

  1. Drag the view by its title bar. Do not release the left mouse button yet.
  2. As you move the view around the Workbench, the mouse pointer changes to one of the drop cursors shown in the table below. The drop cursor indicates where the view will be docked if you release the left mouse button. To see the drop cursor change, drag the view over the left, right, top, or bottom border of another view or editor.
  3. When the view is in the location that you want, relative to the view or editor area underneath the drop cursor, release the left mouse button.
  4. (Optional) If you want to save your changes, select Window > Save Perspective As from the main menu bar.
  5. Note that a group of stacked views can be dragged using the empty space to the right of the view tabs.

Working with the Perl Editor

Syntax Check

EPIC performs on the fly syntax check of Perl source files. In order for the Syntax Check to work the Perl Interpreter has to be set up correctly (see Setting up Preferences).
The Syntax Check is performed after a defined idle period, after the user has stopped typing. This idle period can be configured in the preferences.
When an error/warning has been found the editor displays the appropriate icon in the annotation ruler (the gray bar on the left side of the editor), underlines the error in the source and inserts a marker into the Problems View window.

Syntax Check


Explain Errors and Warnings

In addition to displaying warnings and errors the editor is capable of explaining Errors and Warnings.
To get an Error/Warning explanation right-click the Error/Warning icon and select Explain Errors/Warnings from the dropdown menu.

Explaint Errors/Warnings popup

The explanation(s) will be displayed in the Explain Errors/Warnings View.

Explain Warnings/Errors


Perldoc

To retrieve perldoc information select a keyword or text and choose one of the perldoc options from the context menu.
If nothing is selected an input box will pop up.

Perldoc Context Menu

If a perldoc entry is found it is displayed inside the Perldoc View.

Perldoc View

NOTE: Perldoc has to be installed available in the system PATH, otherwise this feature will not work.

Quick Reference

Apart from Perldoc support a quick reference feature is available. This feature has the advantage that no perldoc has to be installed on the system but does not provide as many information as perldoc.
To view the Quick Reference select a keyword and move the mouse pointer over the selection.
A tooltip with a short description of the keyword should appear.

Quick Reference


Code Assist

Code Assist features try to assist the user during source code editing.

NOTE: The features currently implemented in EPIC may not be fully functional but will be improved in the future.

Variable Inspection

When pressing one of the auto completion characters $ @ % the editor displays all defined variables in a list. From the list the user can select the variable that should be inserted in the source code.

Variable Inspection

Module Inspection

The editor tries to display methods available in modules when the auto completion characters > or : are pressed.


Module Inspection


NOTE:

Currently the Indirect  Object Invocation is not recognized by code assist.

This code block will not work:

$smtp = new Net::SMTP;
$smtp->
[no content assist]

This one will work:

$smtp = Net::SMTP->new(.....);
$smtp->
[content assist]



TODO Markers

TODO Markers are a very convenient way to add  todos to the Eclipse task list.
A TODO marker is generated when a #TODO any text is found in the Perl source code.
On deletion of the #TODO comment, the TODO Marker is also deleted.

TODO Marker


Templates

Templates allow for easy insertion of predefined text segments. In addition to normal text these segments can also include pre-defined variables that are included at runtime as well as variables that are specified by the user when the template is inserted.

Defining Templates

Templates are defined in the EPIC Preferences (Window > Preferences...).
To define a new template press the New... button.


Template Dialog


To insert pre-defined variables press the Insert Variable... button.

Predefined Variables

In addition to pre-defined variables the user can specify additional variables ( using the syntax ${varname} ) which can be edited when the template is inserted. When the first variable is inserted variables with the same name will automatically be changed.

Using Templates

Templates are invoked by typing some characters and pressing Ctrl+Space.
Templates matching the typed characters will be displayed in a list. A preview is also available.

Template Selection

If the template contains user defined variables the user can press the TAB key to jump to the next variable after the template has been inserted.

User Variables

Source Formatter

EPIC uses PerlTidy for source code formatting (PerlTidy is included in the EPIC package).
To format the source code select Source > Format from the Eclipse menu or use Ctrl+shift+f.

PerlTidy settings can be changed in the Source Formatter preference page.

NOTE: Source formatting might take a while if the source code has a lot of lines.

HTML Export

To export select Source > Export > HTML from the Eclipse menu and specify an output file.

HTML export settings can be changed in the Source Formatter preference page.

NOTE: For HTML export to work a working Source Formatter is needed.

Outline View

The Outline View displays modules and subroutines. By clicking on the module/subroutine name the editor will jump to the appropriate position in the source code.
Subroutines named new will get a different icon.

Outline View


Using the Perl Debugger

Launching Perl Programs

You may launch your Perl programs from the workbench.  Programs may be launched in either run or debug mode. The environment a Perl program is to be executed in is defined via "Launch Configurations". A launch configuration defines

Launching Perl programs in run mode



  1. Select Menu->Run
  2. Within the dialog appearing
    select the configuration type:
    Perl(local): Run a Perl script on the local machine
    Perl-CGI(local): Run Perl programs in a CGI environment
    Perl(remote): Run Perl script on a remote machine
    and press the new button to create a new launch configuration.
  3. Adjust  launch configuration attributes. For details see Configuring Launch Configurations   .
  4. Press the "Run" Button
This executes the program. The programs console output will  be shown in the console window. The console window also accepts keyboard input to be passed to the program.

If you switch to the debug view you have additional control over the execution of the program. For details see Debug View .

Launching Perl Programs in debug mode



Before debugging a program you may want to set break points to stop program execution at certain source code locations. For details see Debug View .
  1. Select Menu->Debug
  2. Within the dialog appearing
    select the configuration type:
    Perl(local): Run a Perl script on the local machine
    Perl-CGI(local): Run Perl programs in a CGI environment
    Perl(remote): Run Perl script on a remote machine
    and press the new button to create a new launch configuration.
  3. Adjust  launch configuration attributes. For details see    .
  4. Press the "Debug" Button
If you switch to the debug view you have additional control over the execution of the program. For details see Debug View .

Re-launching a Perl Program

The workbench keeps a history of each launched and debugged program. To relaunch a program, do one of the following:

To relaunch the most recent launch, do one of the following:

Configuring Launch Configurations

Perl(local): Running a Perl script on the local machine



  1. Enter the name for the launch configuration in they "Name" field.
  2. In the "Configuration" tab
    "Project" field: select the project to debug.
    Note: Only Perl projects (projects associated with a Perl nature) will be shown. If the project you require isn't shown see Converting an existing Project  for adding a Perl nature to your project.
    "File to execute" field: select the Perl file to execute.
    Note: Only files associated with the Perl editor will be shown. See Associating Files with the Perl editor for details.
    "Commadline Parameters"
    field: Enter command line parameters to pass to the selected perl script
  3. Press the "Apply" button

Perl-CGI(local): Run Perl programms in a CGI environment


  1. Enter the name for the launch configuration in they "Name" field.
  2. In the "Web Server" tab
    "HTML Root Directory" Field: Enter the base directory that contains all HTML files or use the "Browse" button to select the appropriate directory.
    "HTML Startup File" Field: Enter the file name to be shown in the browser after startup or use  the "Browse" button to select this file.
    "CGI Root Directory" Field: Enter the base directory that contains all CGI files or use the "Browse" button to select the appropriate directory.
    "Extension for CGI files" Field: this is a comma separated list of file extensions (each starting with a  "." ) used  for CGI  files in the project.
  3. In the "CGI Environment" tab
    CGI-Script Environment Variables Field: Sorted  list of environemt vailables to be set  for CGI scripts to be excuted. Use the following syntax to specify environment variables: name=value.
  4. In the "Browser" tab
    There are two possible settings:
    Select "Custom Browser":
    specify the path to the browser executable and add the required command line parameters. Use "%1" as a place holder for the HTML file to be opened.
    Select "Default System Browser":
    to use the browser defined as default browser by your OS preferences.
  5. Press the "Apply" button

Perl(remote): Run Perl script on a remote machine

----Not yet implemented----

Break Points

The Perl debugger supports line break points and regular expression breakpoints. Both types of  breakpoints are set on an executable line of a program. If enabled they suspend thread execution before the corresponding line of code is executed. Regular expression breakpoints additionally extract the regular expression contained in the line of code they are associated with and enable you to debug the regular expression within the RegEx-Plugin.
The following symbols are used to indicate breakpoints :
Status
Line
Break Point
Regular Expression
 Break Point
Enabled


Disabled


Registered with debugger



Note:
Regular Expressions Break Points are still in an experimental state and will at the moment only work for expressions of the type:
Expr1 =~ <delim>regexp<delim>modifier;
Modifiers are ignored.

Setting Break Points

  1. In the editor area, open the file where you want to add the breakpoint with the Perl editor. 
  2.  Directly to the left of the line where you want to add the breakpoint, open the marker bar (vertical ruler) pop-up menu and select Add Breakpoint or Add RegExp Breakpoint.

While the breakpoint is enabled, thread execution suspends before that line of code is executed.


Enabling or  Disabling  Break Points

Open the debug view, open the breakpoint view  and use the check box in front of the break point to enable or disable the break point.

Removing Break Points

There are two possible ways for removing a  breakpoint:
  1. Right click on the breakpoint symbol in marker the bar (vertical ruler) of the editor pop-up menu and select Remove Breakpoint.
  2. Open the debug view, open the breakpoint window (if this window is not visible see Adding and Removing views ), right-click the breakpoint you want to remove and select Remove.

Views in the Debug Perspective

Debug View


This view allows you to manage the debugging or running of  programs in the workbench. It displays the stack frame for the suspended threads for each target you are debugging. Each thread in your program appears as a node in the tree. It also displays the process for each target you are running.

If the thread is suspended, its stack frames are shown as child elements.


Variable View

Variables View

When a stack frame is selected, you can see the visible variables in that stack frame in the Variables view.
The Variables view shows the value of primitive types.  Complex variables can be examined by expanding them to show their members.

Global variables (including Perl internal variables) are marked with an icon,  local variables with an  icon.

If the value of a variable has changed since the last execution step it is displayed in red.
If changes in inner levels of complex  variables have occurred the path to the changed variables is indicated via  delta symbols:


This makes it possible to see these kind of changes even if variables are collapsed.

Customizing the Variables View

You can customize the presentation with the configuration menu.

Show detail pane

To show the detail pane select  "Vertical View Orientation" or "Horizontal View Orientation" .  Select "Variables View Only" to disable it.
The details pane shows the value of  primitive variables (especially useful for string variables).

Select Variables to display

The variables view allows to select the following types of variables for displaying by checking the corresponding menu entry:

Breakpoint View



The breakpoint views shows all breakpoints, their state (see Break Points) and location.
By selecting one ore more break points and invoking the context menu you can enable, disable or remove these break points.

Perl Expression View



The Perl Expression View allows you to execute any valid Perl code within the current context of the program executed in debug mode.

  1. Open the Perl Debug View  (Window->Open View->Other->Epic->Perl Expression View)
  2. Enter the code to execute
  3. Press the symbol

Stepping through the execution of a Perl program

When a thread is suspended, the step controls can be used to step through the execution of the program line-by-line. If a breakpoint is encountered while performing a step operation,  the execution will suspend at the breakpoint and the step operation is ended.

Step over

  1. Select a stack frame in the Debug view. The current line of execution in that stack frame is highlighted in the editor in the Debug perspective.
  2. Click the Step Over button () in the Debug view toolbar, or press the F6 key. The currently-selected line is executed and suspends on the next executable line.

Step into

  1. Select a stack frame in the Debug view. The current line of execution in the selected frame is highlighted in the editor in the Debug perspective.
  2. Click the Step Into () button in the Debug view toolbar, or press the F5 key. The next expression on the currently-selected line to be executed is invoked, and execution suspends at the next executable line in the method that is invoked.

Run to return

  1. Select a stack frame in the Debug view. The current line of execution in the selected frame is highlighted in the editor in the Debug perspective.
  2. Click the Run to Return button () in the Debug view toolbar or press the F7 key. Execution resumes until the next return statement in the current method is executed, and execution suspends on the next executable line.

RegExp Plugin

Enabling the RegExp View

To display the RegExp View select Window > Show View.. > Other... from the Eclipse menu and select the RegExp View from the list.


Show View RegExp

Using the RegExp Plugin

The RegExp plugin is a small tool to debug Regular Expressions.

RegExp View


To check if a Regular Expression is valid, press the run Run icon. If the Regular Expression matches the text i t will be signaled by a green icon.
If the Regular Expression contain brackets the resulting string will be colored.

Debugging Regular Expressions

The Single Step feature allows for a step by step inspection of the regular expression.
If no sub expressions (...) are defined by the user the RegExp Plug-in tries to use logical blocks for matching, otherwise the already existing subexpressions are used.


The following buttons are provided:
 Reset (clears all color markers)
 Step forward
 Step backward

Known Bugs & Problems

Debugger

Problems showing Local Variables

The EPIC debugger uses the PadWalker module to show local (or lexical) variables. PadWalker  0.10 does not display the values for lexical variables declared on  top-level (outside of functions and blocks) correctly if used in debugger mode . To get around this problem put your code within a function:

dummy();

sub dummy
{
    <YOUR CODE>
}


References

Part of this document is taken from the official Eclipse documentation provided by the Eclipse project and IBM.