MDCS: Maple Debugger Client/Server

Version 2.6.4

Table of Contents

• Description
• Screenshot
• Requirements
• Installation
• Configuration
• Usage

Table of Contents

• Description
• Screenshot
• Requirements
• Installation
• Configuration
• Usage

Description

This package provides the client and server for a Maple Debugger Client/Server architecture, an enhancement to the existing Maple debugger. Maple is a computer algebra system sold by Maplesoft.

The server side is an Emacs package with several major modes for displaying and controlling the code that is being debugged. The client side is a Maple package that, when invoked, replaces the Maple library debugger.

The client/server architecture provides several benefits:

• A common, full-featured, debugger interface that can be used whether running Maple from the GUI, the command-line, or from a script.

• Remote debugging--the client (Maple) can be run on one machine, the server on another. Communication is via standard TCP.

• Concurrent debugging--multiple Maple processes can be debugged simultaneously. This permits interactively comparing the actions of different versions of code, or comparing code run on machines with different operating systems. It also permits independently or synchronously stepping through separate processes in a Grid application.

The user interface to the debugger, which is provided by MDS, has the following features:

• The procedure being debugged is displayed in a buffer with font-locking to highlight syntactic elements. If lineinfo data is available for the procedure, the source file itself is used, otherwise an interpreted version of the procedure is displayed.

• Executing the code advances an overlay-arrow that points to the next statement to be executed.

• The output of executed statements and evaluated expressions are displayed in a separate window. These are printed in 1-D format so that they can be saved and reused as Maple input.

• As lines of code are executed, they are echoed in the output window. The result provides a visual trace of all the code that has been executed. Clicking in the output window opens another window that displays the procedure and statement that generated the selected output.

• Expressions can be directly evaluated and displayed in a nice format. For example, a record can be displayed as a vertical list of equations with field name on the left and the entry on the right.

• The common debugging commands, next, into, step, etc., are bound to keystrokes (n, i, s, etc.).

• Breakpoints can be set or cleared directly in the buffer.

• A trace mode permits rapidly tracing through instrumented procedures. That, coupled with the ability to jump from the output to the corresponding statement in the code, facilitates debugging.

• Debugged procedures can be live-patched, that is, modified in-place. This permits testing changes without access to the full source code.

Screenshot

Following is a screen shot of the debugger interface.

• The left pane displays the source file. The marker in the left margin indicates the current statement.
• The top right pane contains output from previously executed statements and a query of the current stack.
• The bottom right pane shows interpreted code for one of the calls on the stack.

Requirements

• GNU Emacs 23.1+ (earlier versions may work)
• maplev-mode 2.33+ (Emacs mode for developing Maple code)
• Maple 14+ (earlier versions should work)

Installation

Copy the files to locations appropriate on your system. Here is where I put the various files:

$HOME/maple/toolbox/mdc/lib    :  mdc.mla mdc.help
$HOME/.emacs.d/maple           :  lisp/mds*.el
$HOME/share/info               :  doc/mds.info (do not include the "doc/")

Under the doc subdirectory is an html format of the mds manual. It may be useful if you do not have Emacs or info installed and so cannot read the info file (mds).

On a Linux system you might be able to install everything with

make install

Configuration

Modify your .emacs file. I have the following

(add-to-list 'load-path (concat user-emacs-directory "maple"))
(autoload 'mds "mds" "Restart the Maple Debugger Server" t)

Usage

Fire up Emacs and launch the server:

M-x mds

Now launch Maple, either tty or the GUI. If libname is set properly, you should be able to access help for the Maple Debugger Client (mdc), by typing ?mdc.

For those in hurry, to debug the int command, do

> mdc(int):
> int(x,x);

If you then go to Emacs, you should see an mds-showstat and mds-output buffer displayed.

In the mds-showstat buffer, type C-h m to get a summary of the available keystrokes.