Editors
Most perspectives in the IDL Workbench are comprised of an editor area and one or more views.
Any number of editors can be open at once, but only one can be active at a time. The main menu bar and toolbar for the IDL Workbench window contain operations that are applicable to the active editor.
Tabs in the editor area indicate the names of resources that are currently open for editing. An asterisk (*) indicates that an editor has unsaved changes.
By default, editors are stacked in the editor area, but you can choose to tile them to view source files simultaneously. See Tiling Editors for instructions.
Here is an example of a text editor in the IDL Workbench:

The gray border at the left margin of the editor area may contain icons that flag errors, warnings, or problems detected by the system. Icons also appear if you have created bookmarks, added breakpoints for debugging, or recorded notes in the Tasks view. You can view details for an icon in the left margin of the editor by moving the mouse pointer over it.
To add an editor window to the current perspective, follow one of the following procedures.
To create a new IDL editor window, click File → IDL Source File.
To change the file type/editor mapping:
- From the Preferences dialog, select the General → Editors → File Associations page.
- Select an extension from the File types list.
- Select an editor from the Associated editors list.
- Click OK.