An example of dylan-environment interactive functionality

Note: dylan-environment is currently only supported on Windows. Unix users may wish to skip this section.

The dylan-environment has a few more options and command groups, which will be presented briefly here:



-ARGUMENTS arguments

Arguments for the project’s application


Open and debug the playground project


Start the project’s application


Debug the project’s application


Profile the execution of the application


Share the console with the application

Command Group



breakpoint commands


debugging commands


memory viewing commands


remote debugging commands


stack commands

The following example demonstrates the console environment’s interactive functionality. In the example, the user starts dylan-environment in interactive mode, opens the playground project, performs some arithmetic, defines a method, and then traces it:

$ dylan-environment
Welcome to Open Dylan, Version 2020.1pre.

For documentation on Open Dylan, see
See for an introduction to the command line tools.

Type "help" for more information.
> play
Opened project gui-dylan-playground
Starting: gui-dylan-playground
? 1 + 2;
  $0 = 3
? define method factorial (x) if (x < 2) 1 else x * factorial(x - 1) end end;
? factorial(5);
  $1 = 120
? :trace factorial
? :set messages verbose
Messages: verbose
? factorial(6);
0: factorial (<object>): (6)
  1: factorial (<object>): (5)
    2: factorial (<object>): (4)
      3: factorial (<object>): (3)
        4: factorial (<object>): (2)
          5: factorial (<object>): (1)
          5: factorial (<object>) => (2)
        4: factorial (<object>) => (6)
      3: factorial (<object>) => (24)
    2: factorial (<object>) => (120)
  1: factorial (<object>) => (720)
0: factorial (<object>) => (#[720])
  $2 = 720
? :exit

The commands described in this appendix can also be used in the Command Line window within the regular Open Dylan development environment. Choose File > Command Line… from the main window and use commands at the ? prompt.