Primitives and EEL Subroutines

In this chapter, we describe all EEL primitives, as well as a few useful EEL subroutines. In Epsilon, the term "primitive" refers to a function or variable that is not written or defined in EEL, but rather built into Epsilon.

It's possible for one command to call another command, as if it were a subroutine with no parameters, but commands are usually written to be called in the context of Epsilon's main loop (see The Main Loop), not from other commands. New Epsilon commands should generally call the functions defined in this chapter, not other commands, except in the case of a new command that simply adds some functionality to an existing single command.

Each section discusses items that pertain to a particular topic, and begins with EEL declarations for the items discussed in that section. If we implemented an item as an EEL subroutine, the declaration often includes a comment that identifies the EEL source file defining the item.

Some EEL primitives have optional parameters. For example, you can call the get_tail() primitive as either get_tail(fname, 1) or get_tail(fname). Any missing parameter automatically takes a value of zero. In this manual, we indicate an optional parameter by showing a ? before it.

When writing EEL extensions, an easy way to look up the documentation on the primitive or subroutine at point is to press F1 F <Enter>. That displays the help in Info mode. Or you can use Shift-F1 to display it in a web browser.

In this chapter:

Buffer Primitives
     Changing Buffer Contents
     Moving Text Between Buffers
     Getting Text from a Buffer
     Spots
     Narrowing
     Undo Primitives
     Searching Primitives
          Regular Expression Searching
          Searching Subroutines
     Moving by Lines
     Other Movement Functions
     Sorting Primitives
     Other Formatting Functions
     Comparing Primitives
     Managing Buffers
     Catching Buffer Changes
     Listing Buffers
Display Primitives
     Creating & Destroying Windows
     Window Resizing Primitives
     Preserving Window Arrangements
     Pop-up Windows
     Pop-up Window Subroutines
     Window Attributes
     Buffer Text in Windows
     Window Titles and Mode Lines
     Normal Buffer Display
          Screen Dimensions
          Character Display
          Character Widths and Columns
     Displaying Status Messages
     Printf-style Format Strings
     Other Display Primitives
     Highlighted Regions
     Character Coloring
     Code Coloring Internals
     Colors
File Primitives
     File Reading Primitives
     File Writing Primitives
     Line Translation Primitives
     Character Encoding Conversions
     More File Primitives
     File Properties
     Low-level File Primitives
     Directories
          Dired Subroutines
     Manipulating File Names
     Internet Primitives
          Parsing URLs
     Tagging Internals
Operating System Primitives
     System Primitives
     Window System Primitives
          WinHelp Interface
          Menu Bar Primitives
          Tool Bar Primitives
          Printing Primitives
     Timing
     Calling Windows DLLs
     Running a Process
          Concurrent Process Primitives
          Other Process Primitives
Control Primitives
     Control Flow
     Character Types
     Examining Strings
     Modifying Strings
     Byte Arrays
     Memory Allocation
     The Name Table
     Built-in and User Variables
     Buffer-specific Variables
     Bytecode Files
     Starting and Finishing
     EEL Debugging and Profiling
     Help Subroutines
Input Primitives
     Keys
     The Mouse
          Mouse Cursors
          Mouse Subroutines
          The Scroll Bar
          Mouse Panning
     Window Events
     Completion Subroutines
          Completion Internals
          Listing Commands & Buffers & Files
     Other Input Functions
     Dialogs
          Standard Dialogs
          Button Dialogs
          Windowed Dialogs
     The Main Loop
     Binding Primitives
Defining Language Modes
     Language-specific Subroutines

Previous Up Next
Syntax Summary Epsilon User's Manual and Reference Changing Buffer Contents