Emacs Lisp

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This is the GNU Emacs Lisp Reference Manual corresponding to Emacs version 24.5.

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.
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.
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.
Generic Commands	Select among command alternatives.
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.
SMIE Customization	Customizing indentation.
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	File sizes, modification times, etc.
Extended Attributes	Extended file attributes for access control.
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.
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.
Decompression	Dealing with compressed data.
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.
Disabling Multibyte	Controlling whether to use multibyte characters.
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.
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	By default, 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.
Size of Displayed Text	How large displayed text is.
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.
Window Dividers	Separating windows visually.
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.
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.
Multi-Frame Images	Some images contain more than one frame.
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.
Desktop Notifications	Desktop notifications.
File Notifications	File 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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