Emacs Lisp

This is the GNU Emacs Lisp Reference Manual corresponding to Emacs version 24.3.

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Introduction Introduction and conventions used.
Lisp Data Types Data types of objects in Emacs Lisp.
Numbers Numbers and arithmetic functions.
Strings and Characters Strings, and functions that work on them.
Lists Lists, cons cells, and related functions.
Sequences Arrays Vectors Lists, strings and vectors are called sequences. Certain functions act on any kind of sequence. The description of vectors is here as well.
Hash Tables Very fast lookup-tables.
Symbols Symbols represent names, uniquely.
Evaluation How Lisp expressions are evaluated.
Control Structures Conditionals, loops, nonlocal exits.
Variables Using symbols in programs to stand for values.
Functions A function is a Lisp program that can be invoked from other functions.
Macros Macros are a way to extend the Lisp language.
Customization Making variables and faces customizable.
Loading Reading files of Lisp code into Lisp.
Byte Compilation Compilation makes programs run faster.
Advising Functions Adding to the definition of a function.
Debugging Tools and tips for debugging Lisp programs.
Read and Print Converting Lisp objects to text and back.
Minibuffers Using the minibuffer to read input.
Command Loop How the editor command loop works, and how you can call its subroutines.
Keymaps Defining the bindings from keys to commands.
Modes Defining major and minor modes.
Documentation Writing and using documentation strings.
Files Accessing files.
Backups and Auto-Saving Controlling how backups and auto-save files are made.
Buffers Creating and using buffer objects.
Windows Manipulating windows and displaying buffers.
Frames Making multiple system-level windows.
Positions Buffer positions and motion functions.
Markers Markers represent positions and update automatically when the text is changed.
Text Examining and changing text in buffers.
Non-ASCII Characters Non-ASCII text in buffers and strings.
Searching and Matching Searching buffers for strings or regexps.
Syntax Tables The syntax table controls word and list parsing.
Abbrevs How Abbrev mode works, and its data structures.
Processes Running and communicating with subprocesses.
Display Features for controlling the screen display.
System Interface Getting the user id, system type, environment variables, and other such things.
Packaging Preparing Lisp code for distribution.
Appendices
Antinews Info for users downgrading to Emacs 23.
GNU Free Documentation License The license for this documentation.
GPL Conditions for copying and changing GNU Emacs.
Tips Advice and coding conventions for Emacs Lisp.
GNU Emacs Internals Building and dumping Emacs; internal data structures.
Standard Errors List of some standard error symbols.
Standard Keymaps List of some standard keymaps.
Standard Hooks List of some standard hook variables.
Index Index including concepts, functions, variables, and other terms.

Detailed Node Listing

Here are other nodes that are subnodes of those already listed, mentioned here so you can get to them in one step:

Introduction
Caveats Flaws and a request for help.
Lisp History Emacs Lisp is descended from Maclisp.
Conventions How the manual is formatted.
Version Info Which Emacs version is running?
Acknowledgments The authors, editors, and sponsors of this manual.
Conventions
Some Terms Explanation of terms we use in this manual.
nil and t How the symbols nil and t are used.
Evaluation Notation The format we use for examples of evaluation.
Printing Notation The format we use when examples print text.
Error Messages The format we use for examples of errors.
Buffer Text Notation The format we use for buffer contents in examples.
Format of Descriptions Notation for describing functions, variables, etc.
Format of Descriptions
A Sample Function Description A description of an imaginary function, foo.
A Sample Variable Description A description of an imaginary variable, electric-future-map.
Lisp Data Types
Printed Representation How Lisp objects are represented as text.
Comments Comments and their formatting conventions.
Programming Types Types found in all Lisp systems.
Editing Types Types specific to Emacs.
Circular Objects Read syntax for circular structure.
Type Predicates Tests related to types.
Equality Predicates Tests of equality between any two objects.
Programming Types
Integer Type Numbers without fractional parts.
Floating Point Type Numbers with fractional parts and with a large range.
Character Type The representation of letters, numbers and control characters.
Symbol Type A multi-use object that refers to a function, variable, or property list, and has a unique identity.
Sequence Type Both lists and arrays are classified as sequences.
Cons Cell Type Cons cells, and lists (which are made from cons cells).
Array Type Arrays include strings and vectors.
String Type An (efficient) array of characters.
Vector Type One-dimensional arrays.
Char-Table Type One-dimensional sparse arrays indexed by characters.
Bool-Vector Type One-dimensional arrays of t or nil.
Hash Table Type Super-fast lookup tables.
Function Type A piece of executable code you can call from elsewhere.
Macro Type A method of expanding an expression into another expression, more fundamental but less pretty.
Primitive Function Type A function written in C, callable from Lisp.
Byte-Code Type A function written in Lisp, then compiled.
Autoload Type A type used for automatically loading seldom-used functions.
Character Type
Basic Char Syntax Syntax for regular characters.
General Escape Syntax How to specify characters by their codes.
Ctl-Char Syntax Syntax for control characters.
Meta-Char Syntax Syntax for meta-characters.
Other Char Bits Syntax for hyper-, super-, and alt-characters.
Cons Cell and List Types
Box Diagrams Drawing pictures of lists.
Dotted Pair Notation A general syntax for cons cells.
Association List Type A specially constructed list.
String Type
Syntax for Strings How to specify Lisp strings.
Non-ASCII in Strings International characters in strings.
Nonprinting Characters Literal unprintable characters in strings.
Text Props and Strings Strings with text properties.
Editing Types
Buffer Type The basic object of editing.
Marker Type A position in a buffer.
Window Type Buffers are displayed in windows.
Frame Type Windows subdivide frames.
Terminal Type A terminal device displays frames.
Window Configuration Type Recording the way a frame is subdivided.
Frame Configuration Type Recording the status of all frames.
Process Type A subprocess of Emacs running on the underlying OS.
Stream Type Receive or send characters.
Keymap Type What function a keystroke invokes.
Overlay Type How an overlay is represented.
Font Type Fonts for displaying text.
Numbers
Integer Basics Representation and range of integers.
Float Basics Representation and range of floating point.
Predicates on Numbers Testing for numbers.
Comparison of Numbers Equality and inequality predicates.
Numeric Conversions Converting float to integer and vice versa.
Arithmetic Operations How to add, subtract, multiply and divide.
Rounding Operations Explicitly rounding floating point numbers.
Bitwise Operations Logical and, or, not, shifting.
Math Functions Trig, exponential and logarithmic functions.
Random Numbers Obtaining random integers, predictable or not.
Strings and Characters
String Basics Basic properties of strings and characters.
Predicates for Strings Testing whether an object is a string or char.
Creating Strings Functions to allocate new strings.
Modifying Strings Altering the contents of an existing string.
Text Comparison Comparing characters or strings.
String Conversion Converting to and from characters and strings.
Formatting Strings format: Emacs's analogue of printf.
Case Conversion Case conversion functions.
Case Tables Customizing case conversion.
Lists
Cons Cells How lists are made out of cons cells.
List-related Predicates Is this object a list? Comparing two lists.
List Elements Extracting the pieces of a list.
Building Lists Creating list structure.
List Variables Modifying lists stored in variables.
Modifying Lists Storing new pieces into an existing list.
Sets And Lists A list can represent a finite mathematical set.
Association Lists A list can represent a finite relation or mapping.
Property Lists A list of paired elements.
Modifying Existing List Structure
Setcar Replacing an element in a list.
Setcdr Replacing part of the list backbone. This can be used to remove or add elements.
Rearrangement Reordering the elements in a list; combining lists.
Property Lists
Plists and Alists Comparison of the advantages of property lists and association lists.
Plist Access Accessing property lists stored elsewhere.
Sequences, Arrays, and Vectors
Sequence Functions Functions that accept any kind of sequence.
Arrays Characteristics of arrays in Emacs Lisp.
Array Functions Functions specifically for arrays.
Vectors Special characteristics of Emacs Lisp vectors.
Vector Functions Functions specifically for vectors.
Char-Tables How to work with char-tables.
Bool-Vectors How to work with bool-vectors.
Rings Managing a fixed-size ring of objects.
Hash Tables
Creating Hash Functions to create hash tables.
Hash Access Reading and writing the hash table contents.
Defining Hash Defining new comparison methods.
Other Hash Miscellaneous.
Symbols
Symbol Components Symbols have names, values, function definitions and property lists.
Definitions A definition says how a symbol will be used.
Creating Symbols How symbols are kept unique.
Symbol Properties Each symbol has a property list for recording miscellaneous information.
Symbol Properties
Symbol Plists Accessing symbol properties.
Standard Properties Standard meanings of symbol properties.
Evaluation
Intro Eval Evaluation in the scheme of things.
Forms How various sorts of objects are evaluated.
Quoting Avoiding evaluation (to put constants in the program).
Backquote Easier construction of list structure.
Eval How to invoke the Lisp interpreter explicitly.
Kinds of Forms
Self-Evaluating Forms Forms that evaluate to themselves.
Symbol Forms Symbols evaluate as variables.
Classifying Lists How to distinguish various sorts of list forms.
Function Indirection When a symbol appears as the car of a list, we find the real function via the symbol.
Function Forms Forms that call functions.
Macro Forms Forms that call macros.
Special Forms "Special forms" are idiosyncratic primitives, most of them extremely important.
Autoloading Functions set up to load files containing their real definitions.
Control Structures
Sequencing Evaluation in textual order.
Conditionals if, cond, when, unless.
Combining Conditions and, or, not.
Iteration while loops.
Nonlocal Exits Jumping out of a sequence.
Nonlocal Exits
Catch and Throw Nonlocal exits for the program's own purposes.
Examples of Catch Showing how such nonlocal exits can be written.
Errors How errors are signaled and handled.
Cleanups Arranging to run a cleanup form if an error happens.
Errors
Signaling Errors How to report an error.
Processing of Errors What Emacs does when you report an error.
Handling Errors How you can trap errors and continue execution.
Error Symbols How errors are classified for trapping them.
Variables
Global Variables Variable values that exist permanently, everywhere.
Constant Variables Certain "variables" have values that never change.
Local Variables Variable values that exist only temporarily.
Void Variables Symbols that lack values.
Defining Variables A definition says a symbol is used as a variable.
Tips for Defining Things you should think about when you define a variable.
Accessing Variables Examining values of variables whose names are known only at run time.
Setting Variables Storing new values in variables.
Variable Scoping How Lisp chooses among local and global values.
Buffer-Local Variables Variable values in effect only in one buffer.
File Local Variables Handling local variable lists in files.
Directory Local Variables Local variables common to all files in a directory.
Variable Aliases Variables that are aliases for other variables.
Variables with Restricted Values Non-constant variables whose value can not be an arbitrary Lisp object.
Generalized Variables Extending the concept of variables.
Scoping Rules for Variable Bindings
Dynamic Binding The default for binding local variables in Emacs.
Dynamic Binding Tips Avoiding problems with dynamic binding.
Lexical Binding A different type of local variable binding.
Using Lexical Binding How to enable lexical binding.
Buffer-Local Variables
Intro to Buffer-Local Introduction and concepts.
Creating Buffer-Local Creating and destroying buffer-local bindings.
Default Value The default value is seen in buffers that don't have their own buffer-local values.
Generalized Variables
Setting Generalized Variables The setf macro.
Adding Generalized Variables Defining new setf forms.
Functions
What Is a Function Lisp functions vs. primitives; terminology.
Lambda Expressions How functions are expressed as Lisp objects.
Function Names A symbol can serve as the name of a function.
Defining Functions Lisp expressions for defining functions.
Calling Functions How to use an existing function.
Mapping Functions Applying a function to each element of a list, etc.
Anonymous Functions Lambda expressions are functions with no names.
Function Cells Accessing or setting the function definition of a symbol.
Closures Functions that enclose a lexical environment.
Obsolete Functions Declaring functions obsolete.
Inline Functions Defining functions that the compiler will expand inline.
Declare Form Adding additional information about a function.
Declaring Functions Telling the compiler that a function is defined.
Function Safety Determining whether a function is safe to call.
Related Topics Cross-references to specific Lisp primitives that have a special bearing on how functions work.
Lambda Expressions
Lambda Components The parts of a lambda expression.
Simple Lambda A simple example.
Argument List Details and special features of argument lists.
Function Documentation How to put documentation in a function.
Macros
Simple Macro A basic example.
Expansion How, when and why macros are expanded.
Compiling Macros How macros are expanded by the compiler.
Defining Macros How to write a macro definition.
Problems with Macros Don't evaluate the macro arguments too many times. Don't hide the user's variables.
Indenting Macros Specifying how to indent macro calls.
Common Problems Using Macros
Wrong Time Do the work in the expansion, not in the macro.
Argument Evaluation The expansion should evaluate each macro arg once.
Surprising Local Vars Local variable bindings in the expansion require special care.
Eval During Expansion Don't evaluate them; put them in the expansion.
Repeated Expansion Avoid depending on how many times expansion is done.
Customization Settings
Common Keywords Common keyword arguments for all kinds of customization declarations.
Group Definitions Writing customization group definitions.
Variable Definitions Declaring user options.
Customization Types Specifying the type of a user option.
Applying Customizations Functions to apply customization settings.
Custom Themes Writing Custom themes.
Customization Types
Simple Types Simple customization types: sexp, integer, etc.
Composite Types Build new types from other types or data.
Splicing into Lists Splice elements into list with :inline.
Type Keywords Keyword-argument pairs in a customization type.
Defining New Types Give your type a name.
Loading
How Programs Do Loading The load function and others.
Load Suffixes Details about the suffixes that load tries.
Library Search Finding a library to load.
Loading Non-ASCII Non-ASCII characters in Emacs Lisp files.
Autoload Setting up a function to autoload.
Repeated Loading Precautions about loading a file twice.
Named Features Loading a library if it isn't already loaded.
Where Defined Finding which file defined a certain symbol.
Unloading How to "unload" a library that was loaded.
Hooks for Loading Providing code to be run when particular libraries are loaded.
Byte Compilation
Speed of Byte-Code An example of speedup from byte compilation.
Compilation Functions Byte compilation functions.
Docs and Compilation Dynamic loading of documentation strings.
Dynamic Loading Dynamic loading of individual functions.
Eval During Compile Code to be evaluated when you compile.
Compiler Errors Handling compiler error messages.
Byte-Code Objects The data type used for byte-compiled functions.
Disassembly Disassembling byte-code; how to read byte-code.
Advising Emacs Lisp Functions
Simple Advice A simple example to explain the basics of advice.
Defining Advice Detailed description of defadvice.
Around-Advice Wrapping advice around a function's definition.
Computed Advice ...is to defadvice as fset is to defun.
Activation of Advice Advice doesn't do anything until you activate it.
Enabling Advice You can enable or disable each piece of advice.
Preactivation Preactivation is a way of speeding up the loading of compiled advice.
Argument Access in Advice How advice can access the function's arguments.
Combined Definition How advice is implemented.
Debugging Lisp Programs
Debugger A debugger for the Emacs Lisp evaluator.
Edebug A source-level Emacs Lisp debugger.
Syntax Errors How to find syntax errors.
Test Coverage Ensuring you have tested all branches in your code.
Profiling Measuring the resources that your code uses.
The Lisp Debugger
Error Debugging Entering the debugger when an error happens.
Infinite Loops Stopping and debugging a program that doesn't exit.
Function Debugging Entering it when a certain function is called.
Explicit Debug Entering it at a certain point in the program.
Using Debugger What the debugger does; what you see while in it.
Debugger Commands Commands used while in the debugger.
Invoking the Debugger How to call the function debug.
Internals of Debugger Subroutines of the debugger, and global variables.
Edebug
Using Edebug Introduction to use of Edebug.
Instrumenting You must instrument your code in order to debug it with Edebug.
Edebug Execution Modes Execution modes, stopping more or less often.
Jumping Commands to jump to a specified place.
Edebug Misc Miscellaneous commands.
Breaks Setting breakpoints to make the program stop.
Trapping Errors Trapping errors with Edebug.
Edebug Views Views inside and outside of Edebug.
Edebug Eval Evaluating expressions within Edebug.
Eval List Expressions whose values are displayed each time you enter Edebug.
Printing in Edebug Customization of printing.
Trace Buffer How to produce trace output in a buffer.
Coverage Testing How to test evaluation coverage.
The Outside Context Data that Edebug saves and restores.
Edebug and Macros Specifying how to handle macro calls.
Edebug Options Option variables for customizing Edebug.
Breaks
Breakpoints Breakpoints at stop points.
Global Break Condition Breaking on an event.
Source Breakpoints Embedding breakpoints in source code.
The Outside Context
Checking Whether to Stop When Edebug decides what to do.
Edebug Display Update When Edebug updates the display.
Edebug Recursive Edit When Edebug stops execution.
Edebug and Macros
Instrumenting Macro Calls The basic problem.
Specification List How to specify complex patterns of evaluation.
Backtracking What Edebug does when matching fails.
Specification Examples To help understand specifications.
Debugging Invalid Lisp Syntax
Excess Open How to find a spurious open paren or missing close.
Excess Close How to find a spurious close paren or missing open.
Reading and Printing Lisp Objects
Streams Intro Overview of streams, reading and printing.
Input Streams Various data types that can be used as input streams.
Input Functions Functions to read Lisp objects from text.
Output Streams Various data types that can be used as output streams.
Output Functions Functions to print Lisp objects as text.
Output Variables Variables that control what the printing functions do.
Minibuffers
Intro to Minibuffers Basic information about minibuffers.
Text from Minibuffer How to read a straight text string.
Object from Minibuffer How to read a Lisp object or expression.
Minibuffer History Recording previous minibuffer inputs so the user can reuse them.
Initial Input Specifying initial contents for the minibuffer.
Completion How to invoke and customize completion.
Yes-or-No Queries Asking a question with a simple answer.
Multiple Queries Asking a series of similar questions.
Reading a Password Reading a password from the terminal.
Minibuffer Commands Commands used as key bindings in minibuffers.
Minibuffer Windows Operating on the special minibuffer windows.
Minibuffer Contents How such commands access the minibuffer text.
Recursive Mini Whether recursive entry to minibuffer is allowed.
Minibuffer Misc Various customization hooks and variables.
Completion
Basic Completion Low-level functions for completing strings.
Minibuffer Completion Invoking the minibuffer with completion.
Completion Commands Minibuffer commands that do completion.
High-Level Completion Convenient special cases of completion (reading buffer names, variable names, etc.).
Reading File Names Using completion to read file names and shell commands.
Completion Variables Variables controlling completion behavior.
Programmed Completion Writing your own completion function.
Completion in Buffers Completing text in ordinary buffers.
Command Loop
Command Overview How the command loop reads commands.
Defining Commands Specifying how a function should read arguments.
Interactive Call Calling a command, so that it will read arguments.
Distinguish Interactive Making a command distinguish interactive calls.
Command Loop Info Variables set by the command loop for you to examine.
Adjusting Point Adjustment of point after a command.
Input Events What input looks like when you read it.
Reading Input How to read input events from the keyboard or mouse.
Special Events Events processed immediately and individually.
Waiting Waiting for user input or elapsed time.
Quitting How C-g works. How to catch or defer quitting.
Prefix Command Arguments How the commands to set prefix args work.
Recursive Editing Entering a recursive edit, and why you usually shouldn't.
Disabling Commands How the command loop handles disabled commands.
Command History How the command history is set up, and how accessed.
Keyboard Macros How keyboard macros are implemented.
Defining Commands
Using Interactive General rules for interactive.
Interactive Codes The standard letter-codes for reading arguments in various ways.
Interactive Examples Examples of how to read interactive arguments.
Input Events
Keyboard Events Ordinary characters--keys with symbols on them.
Function Keys Function keys--keys with names, not symbols.
Mouse Events Overview of mouse events.
Click Events Pushing and releasing a mouse button.
Drag Events Moving the mouse before releasing the button.
Button-Down Events A button was pushed and not yet released.
Repeat Events Double and triple click (or drag, or down).
Motion Events Just moving the mouse, not pushing a button.
Focus Events Moving the mouse between frames.
Misc Events Other events the system can generate.
Event Examples Examples of the lists for mouse events.
Classifying Events Finding the modifier keys in an event symbol. Event types.
Accessing Mouse Functions to extract info from mouse events.
Accessing Scroll Functions to get info from scroll bar events.
Strings of Events Special considerations for putting keyboard character events in a string.
Reading Input
Key Sequence Input How to read one key sequence.
Reading One Event How to read just one event.
Event Mod How Emacs modifies events as they are read.
Invoking the Input Method How reading an event uses the input method.
Quoted Character Input Asking the user to specify a character.
Event Input Misc How to reread or throw away input events.
Keymaps
Key Sequences Key sequences as Lisp objects.
Keymap Basics Basic concepts of keymaps.
Format of Keymaps What a keymap looks like as a Lisp object.
Creating Keymaps Functions to create and copy keymaps.
Inheritance and Keymaps How one keymap can inherit the bindings of another keymap.
Prefix Keys Defining a key with a keymap as its definition.
Active Keymaps How Emacs searches the active keymaps for a key binding.
Searching Keymaps A pseudo-Lisp summary of searching active maps.
Controlling Active Maps Each buffer has a local keymap to override the standard (global) bindings. A minor mode can also override them.
Key Lookup Finding a key's binding in one keymap.
Functions for Key Lookup How to request key lookup.
Changing Key Bindings Redefining a key in a keymap.
Remapping Commands A keymap can translate one command to another.
Translation Keymaps Keymaps for translating sequences of events.
Key Binding Commands Interactive interfaces for redefining keys.
Scanning Keymaps Looking through all keymaps, for printing help.
Menu Keymaps Defining a menu as a keymap.
Menu Keymaps
Defining Menus How to make a keymap that defines a menu.
Mouse Menus How users actuate the menu with the mouse.
Keyboard Menus How users actuate the menu with the keyboard.
Menu Example Making a simple menu.
Menu Bar How to customize the menu bar.
Tool Bar A tool bar is a row of images.
Modifying Menus How to add new items to a menu.
Easy Menu A convenience macro for defining menus.
Defining Menus
Simple Menu Items A simple kind of menu key binding.
Extended Menu Items More complex menu item definitions.
Menu Separators Drawing a horizontal line through a menu.
Alias Menu Items Using command aliases in menu items.
Major and Minor Modes
Hooks How to use hooks; how to write code that provides hooks.
Major Modes Defining major modes.
Minor Modes Defining minor modes.
Mode Line Format Customizing the text that appears in the mode line.
Imenu Providing a menu of definitions made in a buffer.
Font Lock Mode How modes can highlight text according to syntax.
Auto-Indentation How to teach Emacs to indent for a major mode.
Desktop Save Mode How modes can have buffer state saved between Emacs sessions.
Hooks
Running Hooks How to run a hook.
Setting Hooks How to put functions on a hook, or remove them.
Major Modes
Major Mode Conventions Coding conventions for keymaps, etc.
Auto Major Mode How Emacs chooses the major mode automatically.
Mode Help Finding out how to use a mode.
Derived Modes Defining a new major mode based on another major mode.
Basic Major Modes Modes that other modes are often derived from.
Mode Hooks Hooks run at the end of major mode functions.
Tabulated List Mode Parent mode for buffers containing tabulated data.
Generic Modes Defining a simple major mode that supports comment syntax and Font Lock mode.
Example Major Modes Text mode and Lisp modes.
Minor Modes
Minor Mode Conventions Tips for writing a minor mode.
Keymaps and Minor Modes How a minor mode can have its own keymap.
Defining Minor Modes A convenient facility for defining minor modes.
Mode Line Format
Mode Line Basics Basic ideas of mode line control.
Mode Line Data The data structure that controls the mode line.
Mode Line Top The top level variable, mode-line-format.
Mode Line Variables Variables used in that data structure.
%-Constructs Putting information into a mode line.
Properties in Mode Using text properties in the mode line.
Header Lines Like a mode line, but at the top.
Emulating Mode Line Formatting text as the mode line would.
Font Lock Mode
Font Lock Basics Overview of customizing Font Lock.
Search-based Fontification Fontification based on regexps.
Customizing Keywords Customizing search-based fontification.
Other Font Lock Variables Additional customization facilities.
Levels of Font Lock Each mode can define alternative levels so that the user can select more or less.
Precalculated Fontification How Lisp programs that produce the buffer contents can also specify how to fontify it.
Faces for Font Lock Special faces specifically for Font Lock.
Syntactic Font Lock Fontification based on syntax tables.
Multiline Font Lock How to coerce Font Lock into properly highlighting multiline constructs.
Multiline Font Lock Constructs
Font Lock Multiline Marking multiline chunks with a text property.
Region to Refontify Controlling which region gets refontified after a buffer change.
Automatic Indentation of code
SMIE A simple minded indentation engine.
Simple Minded Indentation Engine
SMIE setup SMIE setup and features.
Operator Precedence Grammars A very simple parsing technique.
SMIE Grammar Defining the grammar of a language.
SMIE Lexer Defining tokens.
SMIE Tricks Working around the parser's limitations.
SMIE Indentation Specifying indentation rules.
SMIE Indentation Helpers Helper functions for indentation rules.
SMIE Indentation Example Sample indentation rules.
Documentation
Documentation Basics Where doc strings are defined and stored.
Accessing Documentation How Lisp programs can access doc strings.
Keys in Documentation Substituting current key bindings.
Describing Characters Making printable descriptions of non-printing characters and key sequences.
Help Functions Subroutines used by Emacs help facilities.
Files
Visiting Files Reading files into Emacs buffers for editing.
Saving Buffers Writing changed buffers back into files.
Reading from Files Reading files into buffers without visiting.
Writing to Files Writing new files from parts of buffers.
File Locks Locking and unlocking files, to prevent simultaneous editing by two people.
Information about Files Testing existence, accessibility, size of files.
Changing Files Renaming files, changing permissions, etc.
File Names Decomposing and expanding file names.
Contents of Directories Getting a list of the files in a directory.
Create/Delete Dirs Creating and Deleting Directories.
Magic File Names Special handling for certain file names.
Format Conversion Conversion to and from various file formats.
Visiting Files
Visiting Functions The usual interface functions for visiting.
Subroutines of Visiting Lower-level subroutines that they use.
Information about Files
Testing Accessibility Is a given file readable? Writable?
Kinds of Files Is it a directory? A symbolic link?
Truenames Eliminating symbolic links from a file name.
File Attributes How large is it? Any other names? Etc.
Locating Files How to find a file in standard places.
File Names
File Name Components The directory part of a file name, and the rest.
Relative File Names Some file names are relative to a current directory.
Directory Names A directory's name as a directory is different from its name as a file.
File Name Expansion Converting relative file names to absolute ones.
Unique File Names Generating names for temporary files.
File Name Completion Finding the completions for a given file name.
Standard File Names If your package uses a fixed file name, how to handle various operating systems simply.
File Format Conversion
Format Conversion Overview insert-file-contents and write-region.
Format Conversion Round-Trip Using format-alist.
Format Conversion Piecemeal Specifying non-paired conversion.
Backups and Auto-Saving
Backup Files How backup files are made; how their names are chosen.
Auto-Saving How auto-save files are made; how their names are chosen.
Reverting revert-buffer, and how to customize what it does.
Backup Files
Making Backups How Emacs makes backup files, and when.
Rename or Copy Two alternatives: renaming the old file or copying it.
Numbered Backups Keeping multiple backups for each source file.
Backup Names How backup file names are computed; customization.
Buffers
Buffer Basics What is a buffer?
Current Buffer Designating a buffer as current so that primitives will access its contents.
Buffer Names Accessing and changing buffer names.
Buffer File Name The buffer file name indicates which file is visited.
Buffer Modification A buffer is modified if it needs to be saved.
Modification Time Determining whether the visited file was changed "behind Emacs's back".
Read Only Buffers Modifying text is not allowed in a read-only buffer.
The Buffer List How to look at all the existing buffers.
Creating Buffers Functions that create buffers.
Killing Buffers Buffers exist until explicitly killed.
Indirect Buffers An indirect buffer shares text with some other buffer.
Swapping Text Swapping text between two buffers.
Buffer Gap The gap in the buffer.
Windows
Basic Windows Basic information on using windows.
Windows and Frames Relating windows to the frame they appear on.
Window Sizes Accessing a window's size.
Resizing Windows Changing the sizes of windows.
Splitting Windows Splitting one window into two windows.
Deleting Windows Deleting a window gives its space to other windows.
Recombining Windows Preserving the frame layout when splitting and deleting windows.
Selecting Windows The selected window is the one that you edit in.
Cyclic Window Ordering Moving around the existing windows.
Buffers and Windows Each window displays the contents of a buffer.
Switching Buffers Higher-level functions for switching to a buffer.
Choosing Window How to choose a window for displaying a buffer.
Display Action Functions Subroutines for display-buffer.
Choosing Window Options Extra options affecting how buffers are displayed.
Window History Each window remembers the buffers displayed in it.
Dedicated Windows How to avoid displaying another buffer in a specific window.
Quitting Windows How to restore the state prior to displaying a buffer.
Window Point Each window has its own location of point.
Window Start and End Buffer positions indicating which text is on-screen in a window.
Textual Scrolling Moving text up and down through the window.
Vertical Scrolling Moving the contents up and down on the window.
Horizontal Scrolling Moving the contents sideways on the window.
Coordinates and Windows Converting coordinates to windows.
Window Configurations Saving and restoring the state of the screen.
Window Parameters Associating additional information with windows.
Window Hooks Hooks for scrolling, window size changes, redisplay going past a certain point, or window configuration changes.
Frames
Creating Frames Creating additional frames.
Multiple Terminals Displaying on several different devices.
Frame Parameters Controlling frame size, position, font, etc.
Terminal Parameters Parameters common for all frames on terminal.
Frame Titles Automatic updating of frame titles.
Deleting Frames Frames last until explicitly deleted.
Finding All Frames How to examine all existing frames.
Minibuffers and Frames How a frame finds the minibuffer to use.
Input Focus Specifying the selected frame.
Visibility of Frames Frames may be visible or invisible, or icons.
Raising and Lowering Raising a frame makes it hide other windows; lowering it makes the others hide it.
Frame Configurations Saving the state of all frames.
Mouse Tracking Getting events that say when the mouse moves.
Mouse Position Asking where the mouse is, or moving it.
Pop-Up Menus Displaying a menu for the user to select from.
Dialog Boxes Displaying a box to ask yes or no.
Pointer Shape Specifying the shape of the mouse pointer.
Window System Selections Transferring text to and from other X clients.
Drag and Drop Internals of Drag-and-Drop implementation.
Color Names Getting the definitions of color names.
Text Terminal Colors Defining colors for text terminals.
Resources Getting resource values from the server.
Display Feature Testing Determining the features of a terminal.
Frame Parameters
Parameter Access How to change a frame's parameters.
Initial Parameters Specifying frame parameters when you make a frame.
Window Frame Parameters List of frame parameters for window systems.
Size and Position Changing the size and position of a frame.
Geometry Parsing geometry specifications.
Window Frame Parameters
Basic Parameters Parameters that are fundamental.
Position Parameters The position of the frame on the screen.
Size Parameters Frame's size.
Layout Parameters Size of parts of the frame, and enabling or disabling some parts.
Buffer Parameters Which buffers have been or should be shown.
Management Parameters Communicating with the window manager.
Cursor Parameters Controlling the cursor appearance.
Font and Color Parameters Fonts and colors for the frame text.
Positions
Point The special position where editing takes place.
Motion Changing point.
Excursions Temporary motion and buffer changes.
Narrowing Restricting editing to a portion of the buffer.
Motion
Character Motion Moving in terms of characters.
Word Motion Moving in terms of words.
Buffer End Motion Moving to the beginning or end of the buffer.
Text Lines Moving in terms of lines of text.
Screen Lines Moving in terms of lines as displayed.
List Motion Moving by parsing lists and sexps.
Skipping Characters Skipping characters belonging to a certain set.
Markers
Overview of Markers The components of a marker, and how it relocates.
Predicates on Markers Testing whether an object is a marker.
Creating Markers Making empty markers or markers at certain places.
Information from Markers Finding the marker's buffer or character position.
Marker Insertion Types Two ways a marker can relocate when you insert where it points.
Moving Markers Moving the marker to a new buffer or position.
The Mark How "the mark" is implemented with a marker.
The Region How to access "the region".
Text
Near Point Examining text in the vicinity of point.
Buffer Contents Examining text in a general fashion.
Comparing Text Comparing substrings of buffers.
Insertion Adding new text to a buffer.
Commands for Insertion User-level commands to insert text.
Deletion Removing text from a buffer.
User-Level Deletion User-level commands to delete text.
The Kill Ring Where removed text sometimes is saved for later use.
Undo Undoing changes to the text of a buffer.
Maintaining Undo How to enable and disable undo information. How to control how much information is kept.
Filling Functions for explicit filling.
Margins How to specify margins for filling commands.
Adaptive Fill Adaptive Fill mode chooses a fill prefix from context.
Auto Filling How auto-fill mode is implemented to break lines.
Sorting Functions for sorting parts of the buffer.
Columns Computing horizontal positions, and using them.
Indentation Functions to insert or adjust indentation.
Case Changes Case conversion of parts of the buffer.
Text Properties Assigning Lisp property lists to text characters.
Substitution Replacing a given character wherever it appears.
Registers How registers are implemented. Accessing the text or position stored in a register.
Transposition Swapping two portions of a buffer.
Base 64 Conversion to or from base 64 encoding.
Checksum/Hash Computing cryptographic hashes.
Parsing HTML/XML Parsing HTML and XML.
Atomic Changes Installing several buffer changes "atomically".
Change Hooks Supplying functions to be run when text is changed.
The Kill Ring
Kill Ring Concepts What text looks like in the kill ring.
Kill Functions Functions that kill text.
Yanking How yanking is done.
Yank Commands Commands that access the kill ring.
Low-Level Kill Ring Functions and variables for kill ring access.
Internals of Kill Ring Variables that hold kill ring data.
Indentation
Primitive Indent Functions used to count and insert indentation.
Mode-Specific Indent Customize indentation for different modes.
Region Indent Indent all the lines in a region.
Relative Indent Indent the current line based on previous lines.
Indent Tabs Adjustable, typewriter-like tab stops.
Motion by Indent Move to first non-blank character.
Text Properties
Examining Properties Looking at the properties of one character.
Changing Properties Setting the properties of a range of text.
Property Search Searching for where a property changes value.
Special Properties Particular properties with special meanings.
Format Properties Properties for representing formatting of text.
Sticky Properties How inserted text gets properties from neighboring text.
Lazy Properties Computing text properties in a lazy fashion only when text is examined.
Clickable Text Using text properties to make regions of text do something when you click on them.
Fields The field property defines fields within the buffer.
Not Intervals Why text properties do not use Lisp-visible text intervals.
Non-ASCII Characters
Text Representations How Emacs represents text.
Converting Representations Converting unibyte to multibyte and vice versa.
Selecting a Representation Treating a byte sequence as unibyte or multi.
Character Codes How unibyte and multibyte relate to codes of individual characters.
Character Properties Character attributes that define their behavior and handling.
Character Sets The space of possible character codes is divided into various character sets.
Scanning Charsets Which character sets are used in a buffer?
Translation of Characters Translation tables are used for conversion.
Coding Systems Coding systems are conversions for saving files.
Input Methods Input methods allow users to enter various non-ASCII characters without special keyboards.
Locales Interacting with the POSIX locale.
Coding Systems
Coding System Basics Basic concepts.
Encoding and I/O How file I/O functions handle coding systems.
Lisp and Coding Systems Functions to operate on coding system names.
User-Chosen Coding Systems Asking the user to choose a coding system.
Default Coding Systems Controlling the default choices.
Specifying Coding Systems Requesting a particular coding system for a single file operation.
Explicit Encoding Encoding or decoding text without doing I/O.
Terminal I/O Encoding Use of encoding for terminal I/O.
MS-DOS File Types How DOS "text" and "binary" files relate to coding systems.
Searching and Matching
String Search Search for an exact match.
Searching and Case Case-independent or case-significant searching.
Regular Expressions Describing classes of strings.
Regexp Search Searching for a match for a regexp.
POSIX Regexps Searching POSIX-style for the longest match.
Match Data Finding out which part of the text matched, after a string or regexp search.
Search and Replace Commands that loop, searching and replacing.
Standard Regexps Useful regexps for finding sentences, pages,...
Regular Expressions
Syntax of Regexps Rules for writing regular expressions.
Regexp Example Illustrates regular expression syntax.
Regexp Functions Functions for operating on regular expressions.
Syntax of Regular Expressions
Regexp Special Special characters in regular expressions.
Char Classes Character classes used in regular expressions.
Regexp Backslash Backslash-sequences in regular expressions.
The Match Data
Replacing Match Replacing a substring that was matched.
Simple Match Data Accessing single items of match data, such as where a particular subexpression started.
Entire Match Data Accessing the entire match data at once, as a list.
Saving Match Data Saving and restoring the match data.
Syntax Tables
Syntax Basics Basic concepts of syntax tables.
Syntax Descriptors How characters are classified.
Syntax Table Functions How to create, examine and alter syntax tables.
Syntax Properties Overriding syntax with text properties.
Motion and Syntax Moving over characters with certain syntaxes.
Parsing Expressions Parsing balanced expressions using the syntax table.
Syntax Table Internals How syntax table information is stored.
Categories Another way of classifying character syntax.
Syntax Descriptors
Syntax Class Table Table of syntax classes.
Syntax Flags Additional flags each character can have.
Parsing Expressions
Motion via Parsing Motion functions that work by parsing.
Position Parse Determining the syntactic state of a position.
Parser State How Emacs represents a syntactic state.
Low-Level Parsing Parsing across a specified region.
Control Parsing Parameters that affect parsing.
Abbrevs and Abbrev Expansion
Abbrev Tables Creating and working with abbrev tables.
Defining Abbrevs Specifying abbreviations and their expansions.
Abbrev Files Saving abbrevs in files.
Abbrev Expansion Controlling expansion; expansion subroutines.
Standard Abbrev Tables Abbrev tables used by various major modes.
Abbrev Properties How to read and set abbrev properties. Which properties have which effect.
Abbrev Table Properties How to read and set abbrev table properties. Which properties have which effect.
Processes
Subprocess Creation Functions that start subprocesses.
Shell Arguments Quoting an argument to pass it to a shell.
Synchronous Processes Details of using synchronous subprocesses.
Asynchronous Processes Starting up an asynchronous subprocess.
Deleting Processes Eliminating an asynchronous subprocess.
Process Information Accessing run-status and other attributes.
Input to Processes Sending input to an asynchronous subprocess.
Signals to Processes Stopping, continuing or interrupting an asynchronous subprocess.
Output from Processes Collecting output from an asynchronous subprocess.
Sentinels Sentinels run when process run-status changes.
Query Before Exit Whether to query if exiting will kill a process.
System Processes Accessing other processes running on your system.
Transaction Queues Transaction-based communication with subprocesses.
Network Opening network connections.
Network Servers Network servers let Emacs accept net connections.
Datagrams UDP network connections.
Low-Level Network Lower-level but more general function to create connections and servers.
Misc Network Additional relevant functions for net connections.
Serial Ports Communicating with serial ports.
Byte Packing Using bindat to pack and unpack binary data.
Receiving Output from Processes
Process Buffers If no filter, output is put in a buffer.
Filter Functions Filter functions accept output from the process.
Decoding Output Filters can get unibyte or multibyte strings.
Accepting Output How to wait until process output arrives.
Low-Level Network Access
Network Processes Using make-network-process.
Network Options Further control over network connections.
Network Feature Testing Determining which network features work on the machine you are using.
Packing and Unpacking Byte Arrays
Bindat Spec Describing data layout.
Bindat Functions Doing the unpacking and packing.
Bindat Examples Samples of what bindat.el can do for you!
Emacs Display
Refresh Screen Clearing the screen and redrawing everything on it.
Forcing Redisplay Forcing redisplay.
Truncation Folding or wrapping long text lines.
The Echo Area Displaying messages at the bottom of the screen.
Warnings Displaying warning messages for the user.
Invisible Text Hiding part of the buffer text.
Selective Display Hiding part of the buffer text (the old way).
Temporary Displays Displays that go away automatically.
Overlays Use overlays to highlight parts of the buffer.
Width How wide a character or string is on the screen.
Line Height Controlling the height of lines.
Faces A face defines a graphics style for text characters: font, colors, etc.
Fringes Controlling window fringes.
Scroll Bars Controlling vertical scroll bars.
Display Property Enabling special display features.
Images Displaying images in Emacs buffers.
Buttons Adding clickable buttons to Emacs buffers.
Abstract Display Emacs's Widget for Object Collections.
Blinking How Emacs shows the matching open parenthesis.
Character Display How Emacs displays individual characters.
Beeping Audible signal to the user.
Window Systems Which window system is being used.
Bidirectional Display Display of bidirectional scripts, such as Arabic and Farsi.
The Echo Area
Displaying Messages Explicitly displaying text in the echo area.
Progress Informing user about progress of a long operation.
Logging Messages Echo area messages are logged for the user.
Echo Area Customization Controlling the echo area.
Reporting Warnings
Warning Basics Warnings concepts and functions to report them.
Warning Variables Variables programs bind to customize their warnings.
Warning Options Variables users set to control display of warnings.
Delayed Warnings Deferring a warning until the end of a command.
Overlays
Managing Overlays Creating and moving overlays.
Overlay Properties How to read and set properties. What properties do to the screen display.
Finding Overlays Searching for overlays.
Faces
Face Attributes What is in a face?
Defining Faces How to define a face.
Attribute Functions Functions to examine and set face attributes.
Displaying Faces How Emacs combines the faces specified for a character.
Face Remapping Remapping faces to alternative definitions.
Face Functions How to define and examine faces.
Auto Faces Hook for automatic face assignment.
Basic Faces Faces that are defined by default.
Font Selection Finding the best available font for a face.
Font Lookup Looking up the names of available fonts and information about them.
Fontsets A fontset is a collection of fonts that handle a range of character sets.
Low-Level Font Lisp representation for character display fonts.
Fringes
Fringe Size/Pos Specifying where to put the window fringes.
Fringe Indicators Displaying indicator icons in the window fringes.
Fringe Cursors Displaying cursors in the right fringe.
Fringe Bitmaps Specifying bitmaps for fringe indicators.
Customizing Bitmaps Specifying your own bitmaps to use in the fringes.
Overlay Arrow Display of an arrow to indicate position.
The display Property
Replacing Specs Display specs that replace the text.
Specified Space Displaying one space with a specified width.
Pixel Specification Specifying space width or height in pixels.
Other Display Specs Displaying an image; adjusting the height, spacing, and other properties of text.
Display Margins Displaying text or images to the side of the main text.
Images
Image Formats Supported image formats.
Image Descriptors How to specify an image for use in :display.
XBM Images Special features for XBM format.
XPM Images Special features for XPM format.
GIF Images Special features for GIF format.
TIFF Images Special features for TIFF format.
PostScript Images Special features for PostScript format.
ImageMagick Images Special features available through ImageMagick.
Other Image Types Various other formats are supported.
Defining Images Convenient ways to define an image for later use.
Showing Images Convenient ways to display an image once it is defined.
Animated Images Some image formats can be animated.
Image Cache Internal mechanisms of image display.
Buttons
Button Properties Button properties with special meanings.
Button Types Defining common properties for classes of buttons.
Making Buttons Adding buttons to Emacs buffers.
Manipulating Buttons Getting and setting properties of buttons.
Button Buffer Commands Buffer-wide commands and bindings for buttons.
Abstract Display
Abstract Display Functions Functions in the Ewoc package.
Abstract Display Example Example of using Ewoc.
Character Display
Usual Display The usual conventions for displaying characters.
Display Tables What a display table consists of.
Active Display Table How Emacs selects a display table to use.
Glyphs How to define a glyph, and what glyphs mean.
Glyphless Chars How glyphless characters are drawn.
Operating System Interface
Starting Up Customizing Emacs startup processing.
Getting Out How exiting works (permanent or temporary).
System Environment Distinguish the name and kind of system.
User Identification Finding the name and user id of the user.
Time of Day Getting the current time.
Time Conversion Converting a time from numeric form to calendrical data and vice versa.
Time Parsing Converting a time from numeric form to text and vice versa.
Processor Run Time Getting the run time used by Emacs.
Time Calculations Adding, subtracting, comparing times, etc.
Timers Setting a timer to call a function at a certain time.
Idle Timers Setting a timer to call a function when Emacs has been idle for a certain length of time.
Terminal Input Accessing and recording terminal input.
Terminal Output Controlling and recording terminal output.
Sound Output Playing sounds on the computer's speaker.
X11 Keysyms Operating on key symbols for X Windows.
Batch Mode Running Emacs without terminal interaction.
Session Management Saving and restoring state with X Session Management.
Notifications Desktop notifications.
Dynamic Libraries On-demand loading of support libraries.
Starting Up Emacs
Startup Summary Sequence of actions Emacs performs at startup.
Init File Details on reading the init file.
Terminal-Specific How the terminal-specific Lisp file is read.
Command-Line Arguments How command-line arguments are processed, and how you can customize them.
Getting Out of Emacs
Killing Emacs Exiting Emacs irreversibly.
Suspending Emacs Exiting Emacs reversibly.
Terminal Input
Input Modes Options for how input is processed.
Recording Input Saving histories of recent or all input events.
Preparing Lisp code for distribution
Packaging Basics The basic concepts of Emacs Lisp packages.
Simple Packages How to package a single .el file.
Multi-file Packages How to package multiple files.
Package Archives Maintaining package archives.
Tips and Conventions
Coding Conventions Conventions for clean and robust programs.
Key Binding Conventions Which keys should be bound by which programs.
Programming Tips Making Emacs code fit smoothly in Emacs.
Compilation Tips Making compiled code run fast.
Warning Tips Turning off compiler warnings.
Documentation Tips Writing readable documentation strings.
Comment Tips Conventions for writing comments.
Library Headers Standard headers for library packages.
GNU Emacs Internals
Building Emacs How the dumped Emacs is made.
Pure Storage Kludge to make preloaded Lisp functions shareable.
Garbage Collection Reclaiming space for Lisp objects no longer used.
Memory Usage Info about total size of Lisp objects made so far.
Writing Emacs Primitives Writing C code for Emacs.
Object Internals Data formats of buffers, windows, processes.
Object Internals
Buffer Internals Components of a buffer structure.
Window Internals Components of a window structure.
Process Internals Components of a process structure.

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