Massachusetts Institute of Technology	Professor Albert R. Meyer
6.044J/18.423J: Computability Theory of and with Scheme	Fall, 1998

DrScheme strives to be much more student-friendly than MIT Scheme. In particular, for nonexperts, debugging is much easier in DrScheme than MIT Scheme because DrScheme's error messages are clearer, and they indicate where in the user's source code the error occurred. In addition, DrScheme has "Analysis" commands which, for example, will highlight undefined variables in red and can display arrows from occurrences of variables to their definitions elsewhere in the code. It also has several output modes in addition to the standard one, for example, an output mode which shows sharing in lists, and another output mode in which values are printed as canonical INPUT expressions -- in this mode, for example, the list value which is the result of evaluating (cons 1 (cons (+ 2 3) '())) prints out as (list 1 5). DrScheme also has modern Windows 95 menu control of most features.

DrScheme has extensive online documentation which is, however, not always up to date. Its user interface favors working in a single Scheme file, which can make it less convenient for programs which load multiple files.

If you do use DrScheme, the 6.044 instructor would be very interested to hear what you think of it and to learn of any problems.

EdScheme is available for a free two week trial. (After the two week free trial, you have to buy a copy to continue using EdScheme. It lists for $130 but is promised to be available to 6.044 students for $68.95.)

If you do use EdScheme, the 6.044 instructor would be very interested to hear what you think of it and to learn of any problems.