Peppy provides a fairly standard looking graphical user interface that should be familiar if you’ve used a text editor before. However, there are several unique features that may not be obvious, and these are described here.
Peppy can display multiple top level windows, each of which can display an arbitrary number of tabs. Each tab contains exactly one major mode, which is to say that each tab contains one view of a document.
A major mode is a specific type of user interface window for a particular type of file. For example, the Python Major Mode in the image above shows a typical text editor window with line numbers on the left side, a cursor for typing, and scroll bars for moving back and forward in the document.
Other major modes like HexEdit:
provide a different type of user interface. Some types of major modes are specific to a type of file and some are more general and can be used to edit many types of files.
The menu bar of peppy is dynamic, and is customized depending on the major mode. Switching major modes by changing tabs or loading a new file causes the menu bar to be modified so that it only displays items relevant to the current major mode. This prevents cluttering the user interface with a bunch of grayed out items that don’t apply to what you’re editing at the moment.
The tool bar is likewise dynamic, and shows only those tool bar items that are appropriate to the current major mode. The tool bar may also be turned off if you don’t like a tool bar or if you want a little extra vertical space for the major mode.
All files in peppy are treated as being referenced by a URL, even local files. This abstraction makes it easy to add support for new URL schemes to load files, and for the most part, it makes no difference what scheme has been used to load a file. Currently, thanks to the itools virtual file system, support for loading files over http is provided. Other file system support, like sftp (secure FTP) and fish (files over ssh protocol) is planned.
There are also some built-in schemes, like about: that used for read only documentation, mem: used for an in-memory temporary file system, tar: used for read only access to files contained within tar files, and more esoteric schemes like aptus: which is used in the fractal renderer.
Another unique aspect of peppy is the lengths to which it goes to identify a file. Because most text editors assume that the file that you’re loading is a text file, they don’t spend much time trying to figure out what type of file it really is. They just look at the file extension and assume that it correctly identifies the text within it.
Peppy does take into account the filename and extension when identifying a file, but it doesn’t just do that – it also provides several hooks in the file loading process to examine the URL or the contents of the file to determine what type of file it is. This set of heuristics allows peppy to correctly determine the major mode to use even if the file is incorrectly labeled, or in cases where the same file extension is used for different types of data.
A URL uniquely identifies a file on some file system, and peppy uses the URL as the identifier of a loaded document. Only one copy of a document exists in peppy, but it can have many different views in the user interface. And, even if no more views exist of the document, it is still kept in memory by peppy until you explicitly delete it from memory.
Opened files appear in the Documents menu, and a particular document can be opened in any peppy window by selecting it from the menu. A new tab containing a view of the document will appear, using its default major mode. Deleting the tab only causes the tab to go away; it doesn’t delete the document. Only when closing the document will the document be removed from memory.