You can select the name of a type, method, or field in Magik editor and open a new editor on the implementation of the element.
Open Declaration dialog will appear which will allow you to select particular declaration to open. An editor opens containing the selected element.
Note: If selected name will not be underlined it means the element implementation is not available in GIS session or in local resources. Code navigation is also not available while editing external files (File > Open File...).
Magik Source Code Navigation
Views and Editors
Open Declaration dialog