Scheme—Tips on using DrScheme

• Starting DrScheme on the lab machines There should be an icon in the dock (a red, blue and white circle) that you can click on. If not, under Applications in the Go menu along the top of the screen, choose the “PLT Scheme” folder with the highest version number to access the icon.
• Choosing a language Under “Language” on the menu bar, select “Choose Language...”. In the dialog box that pops up, click on the triangle next to “How to Design Programs” (in the category “Teaching Languages”) to see the choices of teaching languages. Click on “Beginning Student” and then on the “OK” button.
• Help Desk Under ''Help'' on the menu bar, select ''Help Desk''. In the browser window that opens up, click on ''How to Design Programs Languages'' in the category ''Languages''. You can click on ''1.15 Primitive Operations'' for functions in the Beginning Student Language.
• Unhelpful help Avoid using the search box in the Help menu, as it does not confine the search to the documentation.
• Opening a new file Under ''File'' on the menu bar, select ''New'' (or ''New Tab'', if you wish to add tabs to a current window).
• Opening an existing file Under ''File'' on the menu bar, select ''Open...''. This will bring up a window that lets you select a file to open.
• Saving a file Press the ''Save'' button on the window. If this is a new file, you will see a window that lets you choose a name for your file and a directory to put it in.
• Copying from a file You can copy information from one file to another by highlighting text, choosing ''Copy'' in the ''Edit'' menu on the menu bar, clicking on the tab or window of another file, and using ''Paste'' in the ''Edit'' menu on the menu bar. The menu also shows keyboard shortcuts.
• Loading a teachpack A teachpack is a file with Scheme definitions in it. Loading a teachpack means you can use any of the definitions as if they were built-in. Under ''Language'' on the menu bar, select ''Add Teachpack...''. In the left column in the window that pops up ''Preinstalled Teachpacks'', choose the appropriate teachpack from the textbook. For a course teachpack, first download the file (see above). If it is the first time you are installing a course teachpack, click on the button ''Add Teachpack to List''. This will bring up a window that lets you select a file. Once the file has been added to the list, you can select it from the list ''User-installed Teachpacks.''
• Clearing all teachpacks Under ''Language'' on the menu bar, select ''Clear All Teachpacks.''
• Commenting and uncommenting Select a block of text (part of a line, one line, or more) in the Definitions window. Under ''Scheme'' on the menu bar, select ''Comment Out with Semicolons''. You can undo the change using ''Uncomment.'' Do not use comment boxes, or your assignments will be unmarkable.
• Indenting Select a block of text in the Definitions window. Under ''Scheme'' on the menu bar, select ''Reindent''. You can also use ''Reindent All'' to reindent the entire program. To indent a single line, put the cursor on the line and press tab.
• Jumping to a definition In the top left corner of your window is an arrow labelled ''(define ...)''. When you click here, you get a menu of all your definitions. You can choose whether they should be sorted by their order in the file or alphabetically.
• Red for unused code After you have run your program, any unused part of the code will appear in red. This either means that you have parts of the code that are not needed (and should be removed) or that you need to add more tests.