ZSHCONTRIB(1)

NAME
zshcontrib - user contributions to zsh

DESCRIPTION

The Zsh source distribution includes a number of items contributed by the user community. These are not inherently a part of the shell, and some may not be available in every zsh installation. The most significant of these are documented here. For documentation on other contributed items such as shell functions, look for comments in the function source files.

UTILITIES

  Accessing On-Line Help

The key sequence ESC h is normally bound by ZLE to execute the run-help widget (see zshzle(1)). This invokes the run-help command with the command word from the current input line as its argument. By default, run-help is an alias for the man command, so this often fails when the command word is a shell builtin or a user-defined function. By redefining the run-help alias, one can improve the on-line help provided by the shell.

The helpfiles utility, found in the Util directory of the distribution, is a Perl program that can be used to process the zsh manual to produce a separate help file for each shell builtin and for many other shell features as well. The autoloadable run-help function, found in Functions/Misc, searches for these helpfiles and performs several other tests to produce the most complete help possible for the command.

There may already be a directory of help files on your system; look in /usr/share/zsh or /usr/local/share/zsh and subdirectories below those, or ask your system administrator.

To create your own help files with helpfiles, choose or create a directory where the individual command help files will reside. For example, you might choose ~/zsh_help. If you unpacked the zsh distribution in your home directory, you would use the commands:

    mkdir ~/zsh_help
    cd ~/zsh_help
    man zshall | colcrt - | \
    perl ~/zsh-4.2.5/Util/helpfiles

Next, to use the run-help function, you need to add lines something like the following to your .zshrc or equivalent startup file:

    unalias run-help
    autoload run-help
    HELPDIR=~/zsh_help

The HELPDIR parameter tells run-help where to look for the help files. If your system already has a help file directory installed, set HELPDIR to the path of that directory instead.

Note that in order for `autoload run-help' to work, the run-help file must be in one of the directories named in your fpath array (see zshparam(1)). This should already be the case if you have a standard zsh installation; if it is not, copy Functions/Misc/run-help to an appropriate directory.

  Recompiling Functions

If you frequently edit your zsh functions, or periodically update your zsh installation to track the latest developments, you may find that function digests compiled with the zcompile builtin are frequently out of date with respect to the function source files. This is not usually a problem, because zsh always looks for the newest file when loading a function, but it may cause slower shell startup and function loading. Also, if a digest file is explicitly used as an element of fpath, zsh won't check whether any of its source files has changed.

The zrecompile autoloadable function, found in Functions/Misc, can be used to keep function digests up to date.

zrecompile [ -qt ] [ name ... ]
zrecompile [ -qt ] -p args [ -- args ... ]
    This tries to find *.zwc files and automatically re-compile them if at least one of the original files is newer than the compiled file. This works only if the names stored in the compiled files are full paths or are relative to the directory that contains the .zwc file.

    In the first form, each name is the name of a compiled file or a directory containing *.zwc files that should be checked. If no arguments are given, the directories and *.zwc files in fpath are used.

    When -t is given, no compilation is performed, but a return status of zero (true) is set if there are files that need to be re-compiled and non-zero (false) otherwise. The -q option quiets the chatty output that describes what zrecompile is doing.

    Without the -t option, the return status is zero if all files that needed re-compilation could be compiled and non-zero if compilation for at least one of the files failed.

    If the -p option is given, the args are interpreted as one or more sets of arguments for zcompile, separated by `--'. For example:

        zrecompile -p \
                   -R ~/.zshrc -- \
                   -M ~/.zcompdump -- \
                   ~/zsh/comp.zwc ~/zsh/Completion/*/_*

    This compiles ~/.zshrc into ~/.zshrc.zwc if that doesn't exist or if it is older than ~/.zshrc. The compiled file will be marked for reading instead of mapping. The same is done for ~/.zcompdump and ~/.zcompdump.zwc, but this compiled file is marked for mapping. The last line re-creates the file ~/zsh/comp.zwc if any of the files matching the given pattern is newer than it.

    Without the -p option, zrecompile does not create function digests that do not already exist, nor does it add new functions to the digest.

The following shell loop is an example of a method for creating function digests for all functions in your fpath, assuming that you have write permission to the directories:

    for ((i=1; i <= $#fpath; ++i)); do
      dir=$fpath[i]
      zwc=${dir:t}.zwc
      if [[ $dir == (.|..) || $dir == (.|..)/* ]]; then
        continue
      fi
      files=($dir/*(N-.))
      if [[ -w $dir:h && -n $files ]]; then
        files=(${${(M)files%/*/*}#/})
        if ( cd $dir:h &&
             zrecompile -p -U -z $zwc $files ); then
          fpath[i]=$fpath[i].zwc
        fi
      fi
    done

The -U and -z options are appropriate for functions in the default zsh installation fpath; you may need to use different options for your personal function directories.

Once the digests have been created and your fpath modified to refer to them, you can keep them up to date by running zrecompile with no arguments.

  Keyboard Definition

The large number of possible combinations of keyboards, workstations, terminals, emulators, and window systems makes it impossible for zsh to have built-in key bindings for every situation. The zkbd utility, found in Functions/Misc, can help you quickly create key bindings for your configuration.

Run zkbd either as an autoloaded function, or as a shell script:

    zsh -f ~/zsh-4.2.5/Functions/Misc/zkbd

When you run zkbd, it first asks you to enter your terminal type; if the default it offers is correct, just press return. It then asks you to press a number of different keys to determine characteristics of your keyboard and terminal; zkbd warns you if it finds anything out of the ordinary, such as a Delete key that sends neither ^H nor ^?.

The keystrokes read by zkbd are recorded as a definition for an associative array named key, written to a file in the subdirectory .zkbd within either your HOME or ZDOTDIR directory. The name of the file is composed from the TERM, VENDOR and OSTYPE parameters, joined by hyphens.

You may read this file into your .zshrc or another startup file with the "source" or "." commands, then reference the key parameter in bindkey commands, like this:

    source ${ZDOTDIR:-$HOME}/.zkbd/$TERM-$VENDOR-$OSTYPE
    [[ -n ${key[Left]} ]] && bindkey "${key[Left]}" backward-char
    [[ -n ${key[Right]} ]] && bindkey "${key[Right]}" forward-char
    # etc.

Note that in order for `autoload zkbd' to work, the zkdb file must be in one of the directories named in your fpath array (see zshparam(1)). This should already be the case if you have a standard zsh installation; if it is not, copy Functions/Misc/zkbd to an appropriate directory.

  Dumping Shell State

Occasionally you may encounter what appears to be a bug in the shell, particularly if you are using a beta version of zsh or a development release. Usually it is sufficient to send a description of the problem to one of the zsh mailing lists (see zsh(1)), but sometimes one of the zsh developers will need to recreate your environment in order to track the problem down.

The script named reporter, found in the Util directory of the distribution, is provided for this purpose. (It is also possible to autoload reporter, but reporter is not installed in fpath by default.) This script outputs a detailed dump of the shell state, in the form of another script that can be read with `zsh -f' to recreate that state.

To use reporter, read the script into your shell with the `.' command and redirect the output into a file:

    . ~/zsh-4.2.5/Util/reporter > zsh.report

You should check the zsh.report file for any sensitive information such as passwords and delete them by hand before sending the script to the developers. Also, as the output can be voluminous, it's best to wait for the developers to ask for this information before sending it.

You can also use reporter to dump only a subset of the shell state. This is sometimes useful for creating startup files for the first time. Most of the output from reporter is far more detailed than usually is necessary for a startup file, but the aliases, options, and zstyles states may be useful because they include only changes from the defaults. The bindings state may be useful if you have created any of your own keymaps, because reporter arranges to dump the keymap creation commands as well as the bindings for every keymap.

As is usual with automated tools, if you create a startup file with reporter, you should edit the results to remove unnecessary commands. Note that if you're using the new completion system, you should not dump the functions state to your startup files with reporter; use the compdump function instead (see zshcompsys(1)).

reporter [ state ... ]
    Print to standard output the indicated subset of the current shell state. The state arguments may be one or more of:

    all Output everything listed below.
    aliases
        Output alias definitions.
    bindings
        Output ZLE key maps and bindings.
    completion
        Output old-style compctl commands. New completion is covered by functions and zstyles.
    functions
        Output autoloads and function definitions.
    limits
        Output limit commands.
    options
        Output setopt commands.
    styles
        Same as zstyles.
    variables
        Output shell parameter assignments, plus export commands for any environment variables.
    zstyles
        Output zstyle commands.

    If the state is omitted, all is assumed.

With the exception of `all', every state can be abbreviated by any prefix, even a single letter; thus a is the same as aliases, z is the same as zstyles, etc.

PROMPT THEMES

  Installation

You should make sure all the functions from the Functions/Prompts directory of the source distribution are available; they all begin with the string `prompt_' except for the special function`promptinit'. You also need the `colors' function from Functions/Misc. All of these functions may already have been installed on your system; if not, you will need to find them and copy them. The directory should appear as one of the elements of the fpath array (this should already be the case if they were installed), and at least the function promptinit should be autoloaded; it will autoload the rest. Finally, to initialize the use of the system you need to call the promptinit function. The following code in your .zshrc will arrange for this; assume the functions are stored in the directory ~/myfns:

    fpath=(~/myfns $fpath)
    autoload -U promptinit
    promptinit

  Theme Selection

Use the prompt command to select your preferred theme. This command may be added to your .zshrc following the call to promptinit in order to start zsh with a theme already selected.

prompt [ -c | -l ]
prompt [ -p | -h ] [ theme ... ]
prompt [ -s ] theme [ arg ... ]
    Set or examine the prompt theme. With no options and a theme argument, the theme with that name is set as the current theme. The available themes are determined at run time; use the -l option to see a list. The special theme `random' selects at random one of the available themes and sets your prompt to that.

    In some cases the theme may be modified by one or more arguments, which should be given after the theme name. See the help for each theme for descriptions of these arguments.

    Options are:

    -c  Show the currently selected theme and its parameters, if any.
    -l  List all available prompt themes.
    -p  Preview the theme named by theme, or all themes if no theme is given.
    -h  Show help for the theme named by theme, or for the prompt function if no theme is given.
    -s  Set theme as the current theme and save state.

prompt_theme_setup
    Each available theme has a setup function which is called by the prompt function to install that theme. This function may define other functions as necessary to maintain the prompt, including functions used to preview the prompt or provide help for its use. You should not normally call a theme's setup function directly.

ZLE FUNCTIONS

  Widgets

These functions all implement user-defined ZLE widgets (see zshzle(1)) which can be bound to keystrokes in interactive shells. To use them, your .zshrc should contain lines of the form

    autoload function
    zle -N function

followed by an appropriate bindkey command to associate the function with a key sequence. Suggested bindings are described below.

bash-style word functions
    If you are looking for functions to implement moving over and editing words in the manner of bash, where only alphanumeric characters are considered word characters, you can use the functions described in the next section. The following is sufficient:

        autoload -U select-word-style
        select-word-style bash

forward-word-match, backward-word-match
kill-word-match, backward-kill-word-match
transpose-words-match, capitalize-word-match
up-case-word-match, down-case-word-match
select-word-style, match-words-by-style
    The eight `-match' functions are drop-in replacements for the builtin widgets without the suffix. By default they behave in a similar way. However, by the use of styles and the function select-word-style, the way words are matched can be altered.

    The simplest way of configuring the functions is to use select-word-style, which can either be called as a normal function with the appropriate argument, or invoked as a user-defined widget that will prompt for the first character of the word style to be used. The first time it is invoked, the eight -match functions will automatically replace the builtin versions, so they do not need to be loaded explicitly.

    The word styles available are as follows. Only the first character is examined.

    bash
        Word characters are alphanumeric characters only.

    normal
        As in normal shell operation: word characters are alphanumeric characters plus any characters present in the string given by the parameter $WORDCHARS.

    shell
        Words are complete shell command arguments, possibly including complete quoted strings, or any tokens special to the shell.

    whitespace
        Words are any set of characters delimited by whitespace.

    default
        Restore the default settings; this is usually the same as `normal'.

    More control can be obtained using the zstyle command, as described in zshmodules(1). Each style is looked up in the context :zle:widget where widget is the name of the user-defined widget, not the name of the function implementing it, so in the case of the definitions supplied by select-word-style the appropriate contexts are :zle:forward-word, and so on. The function select-word-style itself always defines styles for the context `:zle:*' which can be overridden by more specific (longer) patterns as well as explicit contexts.

    The style word-style specifies the rules to use. This may have the following values.

    normal
        Use the standard shell rules, i.e. alphanumerics and $WORDCHARS, unless overridden by the styles word-chars or word-class.

    specified
        Similar to normal, but only the specified characters, and not also alphanumerics, are considered word characters.

    unspecified
        The negation of specified. The given characters are those which will not be considered part of a word.

    shell
        Words are obtained by using the syntactic rules for generating shell command arguments. In addition, special tokens which are never command arguments such as `()' are also treated as words.

    whitespace
        Words are whitespace-delimited strings of characters.

    The first three of those styles usually use $WORDCHARS, but the value in the parameter can be overridden by the style word-chars, which works in exactly the same way as $WORDCHARS. In addition, the style word-class uses character class syntax to group characters and takes precedence over word-chars if both are set. The word-class style does not include the surrounding brackets of the character class; for example, `-:[:alnum:]' is a valid word-class to include all alphanumerics plus the characters `-' and `:'. Be careful including `]', `^' and `-' as these are special inside character classes.

    The final style is skip-chars. This is mostly useful for transpose-words and similar functions. If set, it gives a count of characters starting at the cursor position which will not be considered part of the word and are treated as space, regardless of what they actually are. For example, if

        zstyle ':zle:transpose-words' skip-chars 1

    has been set, and transpose-words-match is called with the cursor on the X of fooXbar, where X can be any character, then the resulting expression is barXfoo.

    Here are some examples of use of the styles, actually taken from the simplified interface in select-word-style:

        zstyle ':zle:*' word-style standard
        zstyle ':zle:*' word-chars ''

    Implements bash-style word handling for all widgets, i.e. only alphanumerics are word characters; equivalent to setting the parameter WORDCHARS empty for the given context.

        style ':zle:*kill*' word-style space

    Uses space-delimited words for widgets with the word `kill' in the name. Neither of the styles word-chars nor word-class is used in this case.

    The word matching and all the handling of zstyle settings is actually implemented by the function match-words-by-style. This can be used to create new user-defined widgets. The calling function should set the local parameter curcontext to :zle:widget, create the local parameter matched_words and call match-words-by-style with no arguments. On return, matched_words will be set to an array with the elements: (1) the start of the line (2) the word before the cursor (3) any non-word characters between that word and the cursor (4) any non-word character at the cursor position plus any remaining non-word characters before the next word, including all characters specified by the skip-chars style, (5) the word at or following the cursor (6) any non-word characters following that word (7) the remainder of the line. Any of the elements may be an empty string; the calling function should test for this to decide whether it can perform its function.

    It is possible to pass options with arguments to match-words-by-style to override the use of styles. The options are:
    -w  word-style
    -s  skip-chars
    -c  word-class
    -C  word-chars

    For example, match-words-by-style -w shell -c 0 may be used to extract the command argument around the cursor.

delete-whole-word-match
    This is another function which works like the -match functions described immediately above, i.e. using styles to decide the word boundaries. However, it is not a replacement for any existing function.

    The basic behaviour is to delete the word around the cursor. There is no numeric prefix handling; only the single word around the cursor is considered. If the widget contains the string kill, the removed text will be placed in the cutbuffer for future yanking. This can be obtained by defining kill-whole-word-match as follows:

        zle -N kill-whole-word-match delete-whole-word-match

    and then binding the widget kill-whole-word-match.

copy-earlier-word
    This widget works like a combination of insert-last-word and copy-prev-shell-word. Repeated invocations of the widget retrieve earlier words on the relevant history line. With a numeric argument N, insert the Nth word from the history line; N may be negative to count from the end of the line.

    If insert-last-word has been used to retrieve the last word on a previous history line, repeated invocations will replace that word with earlier words from the same line.

    Otherwise, the widget applies to words on the line currently being edited. The widget style can be set to the name of another widget that should be called to retrieve words. This widget must accept the same three arguments as insert-last-word.

cycle-completion-positions
    After inserting an unambiguous string into the command line, the new function based completion system may know about multiple places in this string where characters are missing or differ from at least one of the possible matches. It will then place the cursor on the position it considers to be the most interesting one, i.e. the one where one can disambiguate between as many matches as possible with as little typing as possible.

    This widget allows the cursor to be easily moved to the other interesting spots. It can be invoked repeatedly to cycle between all positions reported by the completion system.

edit-command-line
    Edit the command line using your visual editor, as in ksh.

        bindkey -M vicmd v edit-command-line

history-search-end
    This function implements the widgets history-beginning-search-backward-end and history-beginning-search-forward-end. These commands work by first calling the corresponding builtin widget (see `History Control' in zshzle(1)) and then moving the cursor to the end of the line. The original cursor position is remembered and restored before calling the builtin widget a second time, so that the same search is repeated to look farther through the history.

    Although you autoload only one function, the commands to use it are slightly different because it implements two widgets.

        zle -N history-beginning-search-backward-end \
               history-search-end
        zle -N history-beginning-search-forward-end \
               history-search-end
        bindkey '\e^P' history-beginning-search-backward-end
        bindkey '\e^N' history-beginning-search-forward-end

history-pattern-search
    The function history-pattern-search implements widgets which prompt for a pattern with which to search the history backwards or forwards. The pattern is in the usual zsh format, however the first character may be ^ to anchor the search to the start of the line, and the last character may be $ to anchor the search to the end of the line. If the search was not anchored to the end of the line the cursor is positioned just after the pattern found.

    The commands to create bindable widgets are similar to those in the example immediately above:

        autoload -U history-pattern-search
        zle -N history-pattern-search-backward history-pattern-search
        zle -N history-pattern-search-forward history-pattern-search

up-line-or-beginning-search, down-line-or-beginning-search
    These widgets are similar to the builtin functions up-line-or-search and down-line-or-search: if in a multiline buffer they move up or down within the buffer, otherwise they search for a history line matching the start of the current line. In this case, however, they search for a line which matches the current line up to the current cursor position, in the manner of history-beginning-search-backward and -forward, rather than the first word on the line.

incarg
    Typing the keystrokes for this widget with the cursor placed on or to the left of an integer causes that integer to be incremented by one. With a numeric prefix argument, the number is incremented by the amount of the argument (decremented if the prefix argument is negative). The shell parameter incarg may be set to change the default increment to something other than one.

        bindkey '^X+' incarg

incremental-complete-word
    This allows incremental completion of a word. After starting this command, a list of completion choices can be shown after every character you type, which you can delete with ^H or DEL. Pressing return accepts the completion so far and returns you to normal editing (that is, the command line is not immediately executed). You can hit TAB to do normal completion, ^G to abort back to the state when you started, and ^D to list the matches.

    This works only with the new function based completion system.

        bindkey '^Xi' incremental-complete-word

insert-files
    This function allows you type a file pattern, and see the results of the expansion at each step. When you hit return, all expansions are inserted into the command line.

        bindkey '^Xf' insert-files

narrow-to-region [ -p pre ] [ -P post ]
[ -S statepm | -R statepm ] [ -n ] [ start end ])
narrow-to-region-invisible
    Narrow the editable portion of the buffer to the region between the cursor and the mark, which may be in either order. The region may not be empty.

    narrow-to-region may be used as a widget or called as a function from a user-defined widget; by default, the text outside the editable area remains visible. A recursive-edit is performed and the original widening status is then restored. Various options and arguments are available when it is called as a function.

    The options -p pretext and -P posttext may be used to replace the text before and after the display for the duration of the function; either or both may be an empty string.

    If the option -n is also given, pretext or posttext will only be inserted if there is text before or after the region respectively which will be made invisible.

    Two numeric arguments may be given which will be used instead of the cursor and mark positions.

    The option -S statepm is used to narrow according to the other options while saving the original state in the parameter with name statepm, while the option -R statepm is used to restore the state from the parameter; note in both cases the name of the parameter is required. In the second case, other options and arguments are irrelevant. When this method is used, no recursive-edit is performed; the calling widget should call this function with the option -S, perform its own editing on the command line or pass control to the user via `zle recursive-edit', then call this function with the option -R. The argument statepm must be a suitable name for an ordinary parameter, except that parameters beginning with the prefix _ntr_ are reserved for use within narrow-to-region. Typically the parameter will be local to the calling function.

    narrow-to-region-invisible is a simple widget which calls narrow-to-region with arguments which replace any text outside the region with `...'.

    The display is restored (and the widget returns) upon any zle command which would usually cause the line to be accepted or aborted. Hence an additional such command is required to accept or abort the current line.

    The return status of both widgets is zero if the line was accepted, else non-zero.

    Here is a trivial example of a widget using this feature.
        local state
        narrow-to-region -p $'Editing restricted region\n' \
          -P '' -S state
        zle recursive-edit
        narrow-to-region -R state

predict-on
    This set of functions implements predictive typing using history search. After predict-on, typing characters causes the editor to look backward in the history for the first line beginning with what you have typed so far. After predict-off, editing returns to normal for the line found. In fact, you often don't even need to use predict-off, because if the line doesn't match something in the history, adding a key performs standard completion, and then inserts itself if no completions were found. However, editing in the middle of a line is liable to confuse prediction; see the toggle style below.

    With the function based completion system (which is needed for this), you should be able to type TAB at almost any point to advance the cursor to the next ``interesting'' character position (usually the end of the current word, but sometimes somewhere in the middle of the word). And of course as soon as the entire line is what you want, you can accept with return, without needing to move the cursor to the end first.

    The first time predict-on is used, it creates several additional widget functions:

    delete-backward-and-predict
        Replaces the backward-delete-char widget. You do not need to bind this yourself.
    insert-and-predict
        Implements predictive typing by replacing the self-insert widget. You do not need to bind this yourself.
    predict-off
        Turns off predictive typing.

    Although you autoload only the predict-on function, it is necessary to create a keybinding for predict-off as well.

        zle -N predict-on
        zle -N predict-off
        bindkey '^X^Z' predict-on
        bindkey '^Z' predict-off

read-from-minibuffer
    This is most useful when called as a function from inside a widget, but will work correctly as a widget in its own right. It prompts for a value below the current command line; a value may be input using all of the standard zle operations (and not merely the restricted set available when executing, for example, execute-named-cmd). The value is then returned to the calling function in the parameter $REPLY and the editing buffer restored to its previous state. If the read was aborted by a keyboard break (typically ^G), the function returns status 1 and $REPLY is not set.

    If one argument is supplied to the function it is taken as a prompt, otherwise `? ' is used. If two arguments are supplied, they are the prompt and the initial value of $LBUFFER, and if a third argument is given it is the initial value of $RBUFFER. This provides a default value and starting cursor placement. Upon return the entire buffer is the value of $REPLY.

    One option is available: `-k num' specifies that num characters are to be read instead of a whole line. The line editor is not invoked recursively in this case, so depending on the terminal settings the input may not be visible, and only the input keys are placed in $REPLY, not the entire buffer. Note that unlike the read builtin num must be given; there is no default.

    The name is a slight misnomer, as in fact the shell's own minibuffer is not used. Hence it is still possible to call executed-named-cmd and similar functions while reading a value.

replace-string, replace-pattern
    The function replace-string implements two widgets. If defined under the same name as the function, it prompts for two strings; the first (source) string will be replaced by the second everywhere it occurs in the line editing buffer.

    If the widget name contains the word `pattern', for example by defining the widget using the command `zle -N replace-pattern replace-string', then the replacement is done by pattern matching. All zsh extended globbing patterns can be used in the source string; note that unlike filename generation the pattern does not need to match an entire word, nor do glob qualifiers have any effect. In addition, the replacement string can contain parameter or command substitutions. Furthermore, a `&' in the replacement string will be replaced with the matched source string, and a backquoted digit `\N' will be replaced by the Nth parenthesised expression matched. The form `\{N}' may be used to protect the digit from following digits.

    For example, starting from the line:

        print This line contains fan and fond

    and invoking replace-pattern with the source string `f(?)n' and the replacment string `c\1r' produces the not very useful line:

        print This line contains car and cord

    The range of the replacement string can be limited by using the narrow-to-region-invisible widget. One limitation of the current version is that undo will cycle through changes to the replacement and source strings before undoing the replacement itself.

smart-insert-last-word
    This function may replace the insert-last-word widget, like so:

        zle -N insert-last-word smart-insert-last-word

    With a numeric prefix, or when passed command line arguments in a call from another widget, it behaves like insert-last-word, except that words in comments are ignored when INTERACTIVE_COMMENTS is set.

    Otherwise, the rightmost ``interesting'' word from the previous command is found and inserted. The default definition of ``interesting'' is that the word contains at least one alphabetic character, slash, or backslash. This definition may be overridden by use of the match style. The context used to look up the style is the widget name, so usually the context is :insert-last-word. However, you can bind this function to different widgets to use different patterns:

        zle -N insert-last-assignment smart-insert-last-word
        zstyle :insert-last-assignment match '[[:alpha:]][][[:alnum:]]#=*'
        bindkey '\e=' insert-last-assignment

  Styles

The behavior of several of the above widgets can be controlled by the use of the zstyle mechanism. In particular, widgets that interact with the completion system pass along their context to any completions that they invoke.

break-keys
    This style is used by the incremental-complete-word widget. Its value should be a pattern, and all keys matching this pattern will cause the widget to stop incremental completion without the key having any further effect. Like all styles used directly by incremental-complete-word, this style is looked up using the context `:incremental'.

completer
    The incremental-complete-word and insert-and-predict widgets set up their top-level context name before calling completion. This allows one to define different sets of completer functions for normal completion and for these widgets. For example, to use completion, approximation and correction for normal completion, completion and correction for incremental completion and only completion for prediction one could use:

        zstyle ':completion:*' completer \
                _complete _correct _approximate
        zstyle ':completion:incremental:*' completer \
                _complete _correct
        zstyle ':completion:predict:*' completer \
                _complete

    It is a good idea to restrict the completers used in prediction, because they may be automatically invoked as you type. The _list and _menu completers should never be used with prediction. The _approximate, _correct, _expand, and _match completers may be used, but be aware that they may change characters anywhere in the word behind the cursor, so you need to watch carefully that the result is what you intended.

cursor
    The insert-and-predict widget uses this style, in the context `:predict', to decide where to place the cursor after completion has been tried. Values are:

    complete
        The cursor is left where it was when completion finished, but only if it is after a character equal to the one just inserted by the user. If it is after another character, this value is the same as `key'.

    key The cursor is left after the nth occurrence of the character just inserted, where n is the number of times that character appeared in the word before completion was attempted. In short, this has the effect of leaving the cursor after the character just typed even if the completion code found out that no other characters need to be inserted at that position.

    Any other value for this style unconditionally leaves the cursor at the position where the completion code left it.

list
    When using the incremental-complete-word widget, this style says if the matches should be listed on every key press (if they fit on the screen). Use the context prefix `:completion:incremental'.

    The insert-and-predict widget uses this style to decide if the completion should be shown even if there is only one possible completion. This is done if the value of this style is the string always. In this case the context is `:predict' (not `:completion:predict').

match
    This style is used by smart-insert-last-word to provide a pattern (using full EXTENDED_GLOB syntax) that matches an interesting word. The context is the name of the widget to which smart-insert-last-word is bound (see above). The default behavior of smart-insert-last-word is equivalent to:

        zstyle :insert-last-word match '*[[:alpha:]/\\]*'

    However, you might want to include words that contain spaces:

        zstyle :insert-last-word match '*[[:alpha:][:space:]/\\]*'

    Or include numbers as long as the word is at least two characters long:

        zstyle :insert-last-word match '*([[:digit:]]?|[[:alpha:]/\\])*'

    The above example causes redirections like "2>" to be included.

prompt
    The incremental-complete-word widget shows the value of this style in the status line during incremental completion. The string value may contain any of the following substrings in the manner of the PS1 and other prompt parameters:

    %c  Replaced by the name of the completer function that generated the matches (without the leading underscore).

    %l  When the list style is set, replaced by `...' if the list of matches is too long to fit on the screen and with an empty string otherwise. If the list style is `false' or not set, `%l' is always removed.

    %n  Replaced by the number of matches generated.

    %s  Replaced by `-no match-', `-no prefix-', or an empty string if there is no completion matching the word on the line, if the matches have no common prefix different from the word on the line, or if there is such a common prefix, respectively.

    %u  Replaced by the unambiguous part of all matches, if there is any, and if it is different from the word on the line.

    Like `break-keys', this uses the `:incremental' context.

stop-keys
    This style is used by the incremental-complete-word widget. Its value is treated similarly to the one for the break-keys style (and uses the same context: `:incremental'). However, in this case all keys matching the pattern given as its value will stop incremental completion and will then execute their usual function.

toggle
    This boolean style is used by predict-on and its related widgets in the context `:predict'. If set to one of the standard `true' values, predictive typing is automatically toggled off in situations where it is unlikely to be useful, such as when editing a multi-line buffer or after moving into the middle of a line and then deleting a character. The default is to leave prediction turned on until an explicit call to predict-off.

verbose
    This boolean style is used by predict-on and its related widgets in the context `:predict'. If set to one of the standard `true' values, these widgets display a message below the prompt when the predictive state is toggled. This is most useful in combination with the toggle style. The default does not display these messages.

widget
    This style is similar to the command style: For widget functions that use zle to call other widgets, this style can sometimes be used to override the widget which is called. The context for this style is the name of the calling widget (not the name of the calling function, because one function may be bound to multiple widget names).

        zstyle :copy-earlier-word widget smart-insert-last-word

    Check the documentation for the calling widget or function to determine whether the widget style is used.

MIME FUNCTIONS

Three functions are available to provide handling of files recognised by extension, for example to dispatch a file text.ps when executed as a command to an appropriate viewer.

zsh-mime-setup [-flv]
zsh-mime-handler
    These two functions use the files ~/.mime.types and /etc/mime.types, which associate types and extensions, as well as ~/.mailcap and /etc/mailcap files, which associate types and the programs that handle them. These are provided on many systems with the Multimedia Internet Mail Extensions.

    To enable the system, the function zsh-mime-setup should be autoloaded and run. This allows files with extensions to be treated as executable; such files be completed by the function completion system. The function zsh-mime-handler should not need to be called by the user.

    The system works by setting up suffix aliases with `alias -s'. Suffix aliases already installed by the user will not be overwritten.

    Repeated calls to zsh-mime-setup do not override the existing mapping between suffixes and executable files unless the option -f is given. Note, however, that this does not override existing suffix aliases assigned to handlers other than zsh-mime-handler. Calling zsh-mime-setup with the option -l lists the existing mappings without altering them. Calling zsh-mime-setup with the option -v causes verbose output to be shown during the setup operation.

    The system respects the mailcap flags needsterminal and copiousoutput, see mailcap(4).

    The functions use the following styles, which are defined with the zstyle builtin command (see zshmodules(1)). They should be defined before zsh-mime-setup is run. The contexts used all start with :mime:, with additional components in some cases. It is recommended that a trailing * (suitably quoted) be appended to style patterns in case the system is extended in future. Some examples are given below.
    mime-types
        A list of files in the format of ~/.mime.types and /etc/mime.types to be read during setup, replacing the default list which consists of those two files. The context is :mime:. A + in the list will be replaced by the default files.

    mailcap
        A list of files in the format of ~/.mailcap and /etc/mailcap to be read during setup, replacing the default list which consists of those two files. The context is :mime:. A + in the list will be replaced by the default files.

    handler
        Specifies a handler for a suffix; the suffix is given by the context as :mime:.suffix:, and the format of the handler is exactly that in mailcap. Note in particular the `.' and trailing colon to distinguish this use of the context. This overrides any handler specified by the mailcap files. If the handler requires a terminal, the flags style should be set to include the word needsterminal, or if the output is to be displayed through a pager (but not if the handler is itself a pager), it should include copiousoutput.

    flags
        Defines flags to go with a handler; the context is as for the handler style, and the format is as for the flags in mailcap.

    pager
        If set, will be used instead of $PAGER or more to handle suffixes where the copiousoutput flag is set. The context is as for handler, i.e. :mime:.suffix: for handling a file with the given suffix.

    Examples:

        zstyle ':mime:*' mailcap ~/.mailcap /usr/local/etc/mailcap
        zstyle ':mime:.txt:' handler less %s
        zstyle ':mime:.txt:' flags needsterminal

    When zsh-mime-setup is subsequently run, it will look for mailcap entries in the two files given. Files of suffix .txt will be handled by running `less file.txt'. The flag needsterminal is set to show that this program must run attached to a terminal.

    As there are several steps to dispatching a command, the following should be checked if attempting to execute a file by extension .ext does not have the expected effect.

    The command `alias -s ext' should show
        `ps=zsh-mime-handler'. If it shows something else, another suffix alias was already installed and was not overwritten. If it shows nothing, no handler was installed: this is most likely because no handler was found in the .mime.types and mailcap combination for .ext files. In that case, appropriate handling should be added to ~/.mime.types and mailcap.

    If the extension is handled by zsh-mime-handler but the file is
        not opened correctly, either the handler defined for the type is incorrect, or the flags associated with it are in appropriate. Running zsh-mime-setup -l will show the handler and, if there are any, the flags. A %s in the handler is replaced by the file (suitably quoted if necessary). Check that the handler program listed lists and can be run in the way shown. Also check that the flags needsterminal or copiousoutput are set if the handler needs to be run under a terminal; the second flag is used if the output should be sent to a pager. An example of a suitable mailcap entry for such a program is:

            text/html; /usr/bin/lynx '%s'; needsterminal

pick-web-browser
    This function is separate from the two MIME functions described above and can be assigned directly to a suffix:

        autoload -U pick-web-browser
        alias -s html=pick-web-browser

    It is provided as an intelligent front end to dispatch a web browser. It will check if an X Windows display is available, and if so if there is already a browser running which can accept a remote connection. In that case, the file will be displayed in that browser; you should check explicitly if it has appeared in the running browser's window. Otherwise, it will start a new browser according to a builtin set of preferences.

    Alternatively, pick-web-browser can be run as a zsh script.

    Two styles are available to customize the choice of browsers: x-browsers when running under the X Windows System, and tty-browsers otherwise. These are arrays in decreasing order of preference consiting of the command name under which to start the browser. They are looked up in the context :mime: (which may be extended in future, so appending `*' is recommended). For example,

        zstyle ':mime:*' x-browsers opera konqueror netscape

    specifies that pick-web-browser should first look for a runing instance of Opera, Konqueror or Netscape, in that order, and if it fails to find any should attempt to start Opera.

OTHER FUNCTIONS

There are a large number of helpful functions in the Functions/Misc directory of the zsh distribution. Most are very simple and do not require documentation here, but a few are worthy of special mention.

  Descriptions

colors
    This function initializes several associative arrays to map color names to (and from) the ANSI standard eight-color terminal codes. These are used by the prompt theme system (see above). You seldom should need to run colors more than once.

    The eight base colors are: black, red, green, yellow, blue, magenta, cyan, and white. Each of these has codes for foreground and background. In addition there are eight intensity attributes: bold, faint, standout, underline, blink, reverse, and conceal. Finally, there are six codes used to negate attributes: none (reset all attributes to the defaults), normal (neither bold nor faint), no-standout, no-underline, no-blink, and no-reverse.

    Some terminals do not support all combinations of colors and intensities.

    The associative arrays are:

    color
    colour
        Map all the color names to their integer codes, and integer codes to the color names. The eight base names map to the foreground color codes, as do names prefixed with `fg-', such as `fg-red'. Names prefixed with `bg-', such as `bg-blue', refer to the background codes. The reverse mapping from code to color yields base name for foreground codes and the bg- form for backgrounds.

        Although it is a misnomer to call them `colors', these arrays also map the other fourteen attributes from names to codes and codes to names.

    fg
    fg_bold
    fg_no_bold
        Map the eight basic color names to ANSI terminal escape sequences that set the corresponding foreground text properties. The fg sequences change the color without changing the eight intensity attributes.

    bg
    bg_bold
    bg_no_bold
        Map the eight basic color names to ANSI terminal escape sequences that set the corresponding background properties. The bg sequences change the color without changing the eight intensity attributes.

    In addition, the scalar parameters reset_color and bold_color are set to the ANSI terminal escapes that turn off all attributes and turn on bold intensity, respectively.

fned name
    Same as zed -f. This function does not appear in the zsh distribution, but can be created by linking zed to the name fned in some directory in your fpath.

is-at-least needed [ present ]
    Perform a greater-than-or-equal-to comparison of two strings having the format of a zsh version number; that is, a string of numbers and text with segments separated by dots or dashes. If the present string is not provided, $ZSH_VERSION is used. Segments are paired left-to-right in the two strings with leading non-number parts ignored. If one string has fewer segments than the other, the missing segments are considered zero.

    This is useful in startup files to set options and other state that are not available in all versions of zsh.

        is-at-least 3.1.6-15 && setopt NO_GLOBAL_RCS
        is-at-least 3.1.0 && setopt HIST_REDUCE_BLANKS
        is-at-least 2.6-17 || print "You can't use is-at-least here."

nslookup [ arg ... ]
    This wrapper function for the nslookup command requires the zsh/zpty module (see zshmodules(1)). It behaves exactly like the standard nslookup except that it provides customizable prompts (including a right-side prompt) and completion of nslookup commands, host names, etc. (if you use the function-based completion system). Completion styles may be set with the context prefix `:completion:nslookup'.

    See also the pager, prompt and rprompt styles below.

run-help
    See `Accessing On-Line Help' above.

tetris
    Zsh was once accused of not being as complete as Emacs, because it lacked a Tetris game. This function was written to refute this vicious slander.

    This function must be used as a ZLE widget:

        autoload -U tetris
        zle -N tetris
        bindkey keys tetris

    To start a game, execute the widget by typing the keys. Whatever command line you were editing disappears temporarily, and your keymap is also temporarily replaced by the Tetris control keys. The previous editor state is restored when you quit the game (by pressing `q') or when you lose.

    If you quit in the middle of a game, the next invocation of the tetris widget will continue where you left off. If you lost, it will start a new game.

zargs [ option ... -- ] [ input ... ] [ -- command [ arg ... ] ]
    This function works like GNU xargs, except that instead of reading lines of arguments from the standard input, it takes them from the command line. This is useful because zsh, especially with recursive glob operators, often can construct a command line for a shell function that is longer than can be accepted by an external command.

    The option list represents options of the zargs command itself, which are the same as those of xargs. The input list is the collection of strings (often file names) that become the arguments of the command, analogous to the standard input of xargs. Finally, the arg list consists of those arguments (usually options) that are passed to the command each time it runs. The arg list precedes the elements from the input list in each run. If no command is provided, then no arg list may be provided, and in that event the default command is `print' with arguments `-r --'.

    For example, to get a long ls listing of all plain files in the current directory or its subdirectories:

        autoload -U zargs
        zargs -- **/*(.) -- ls -l

    Note that `--' is used both to mark the end of the option list and to mark the end of the input list, so it must appear twice whenever the input list may be empty. If there is guaranteed to be at least one input and the first input does not begin with a `-', then the first `--' may be omitted.

    In the event that the string `--' is or may be an input, the -e option may be used to change the end-of-inputs marker. Note that this does not change the end-of-options marker. For example, to use `..' as the marker:

        zargs -e.. -- **/*(.) .. ls -l

    This is a good choice in that example because no plain file can be named `..', but the best end-marker depends on the circumstances.

    For details of the other zargs options, see xargs(1) or run zargs with the --help option.

zcalc [ expression ... ]
    A reasonably powerful calculator based on zsh's arithmetic evaluation facility. The syntax is similar to that of formulae in most programming languages; see the section `Arithmetic Evaluation' in zshmisc(1) for details. The mathematical library zsh/mathfunc will be loaded if it is available; see the section `The zsh/mathfunc Module' in zshmodules(1). The mathematical functions correspond to the raw system libraries, so trigonometric functions are evaluated using radians, and so on.

    Each line typed is evaluated as an expression. The prompt shows a number, which corresponds to a positional parameter where the result of that calculation is stored. For example, the result of the calculation on the line preceded by `4> ' is available as $4. Full command line editing, including the history of previous calculations, is available; the history is saved in the file ~/.zcalc_history. To exit, enter a blank line or type `q' on its own.

    If arguments are given to zcalc on start up, they are used to prime the first few positional parameters. A visual indication of this is given when the calculator starts.

    The constants PI (3.14159...) and E (2.71828...) are provided. Parameter assignment is possible, but note that all parameters will be put into the global namespace.

    An extra facility is provided for changing the default output base. Use, for example, `[#16]' to display hexadecimal output preceded by an indication of the base, or `[##16]' just to display the raw number in the given base. Bases themselves are always specified in decimal. `[#]' restores the normal output format.

    The output base can be initialised by passing the option `-#base', for example `zcalc -#16' (the `#' may have to be quoted, depending on the globbing options set).

    The prompt is configurable via the parameter ZCALCPROMPT, which undergoes standard prompt expansion. The index of the current entry is stored locally in the first element of the array psvar, which can be referred to in ZCALCPROMPT as `%1v'. The default prompt is `%1v> '.

    See the comments in the function for a few extra tips.

zed [ -f ] name
zed -b
    This function uses the ZLE editor to edit a file or function.

    Only one name argument is allowed. If the -f option is given, the name is taken to be that of a function; if the function is marked for autoloading, zed searches for it in the fpath and loads it. Note that functions edited this way are installed into the current shell, but not written back to the autoload file.

    Without -f, name is the path name of the file to edit, which need not exist; it is created on write, if necessary.

    While editing, the function sets the main keymap to zed and the vi command keymap to zed-vicmd. These will be copied from the existing main and vicmd keymaps if they do not exist the first time zed is run. They can be used to provide special key bindings used only in zed.

    If it creates the keymap, zed rebinds the return key to insert a line break and `^X^W' to accept the edit in the zed keymap, and binds `ZZ' to accept the edit in the zed-vicmd keymap.

    The bindings alone can be installed by running `zed -b'. This is suitable for putting into a startup file. Note that, if rerun, this will overwrite the existing zed and zed-vicmd keymaps.

    Completion is available, and styles may be set with the context prefix `:completion:zed'.

    A zle widget zed-set-file-name is available. This can be called by name from within zed using `\ex zed-set-file-name' (note, however, that because of zed's rebindings you will have to type ^j at the end instead of the return key), or can be bound to a key in either of the zed or zed-vicmd keymaps after `zed -b' has been run. When the widget is called, it prompts for a new name for the file being edited. When zed exits the file will be written under that name and the original file will be left alone. The widget has no effect with `zed -f'.

    While zed-set-file-name is running, zed uses the keymap zed-normal-keymap, which is linked from the main keymap in effect at the time zed initialised its bindings. (This is to make the return key operate normally.) The result is that if the main keymap has been changed, the widget won't notice. This is not a concern for most users.

zcp [ -finqQvwW ] srcpat dest
zln [ -finqQsvwW ] srcpat dest
    Same as zmv -C and zmv -L, respectively. These functions do not appear in the zsh distribution, but can be created by linking zmv to the names zcp and zln in some directory in your fpath.

zkbd
    See `Keyboard Definition' above.

zmv [ -finqQsvwW ] [ -C | -L | -M | -p program ] [ -o optstring ] srcpat dest
    Move (usually, rename) files matching the pattern srcpat to corresponding files having names of the form given by dest, where srcpat contains parentheses surrounding patterns which will be replaced in turn by $1, $2, ... in dest. For example,

        zmv '(*).lis' '$1.txt'

    renames `foo.lis' to `foo.txt', `my.old.stuff.lis' to `my.old.stuff.txt', and so on.

    The pattern is always treated as an EXTENDED_GLOB pattern. Any file whose name is not changed by the substitution is simply ignored. Any error (a substitution resulted in an empty string, two substitutions gave the same result, the destination was an existing regular file and -f was not given) causes the entire function to abort without doing anything.

    Options:

    -f  Force overwriting of destination files. Not currently passed down to the mv/cp/ln command due to vagaries of implementations (but you can use -o-f to do that).
    -i  Interactive: show each line to be executed and ask the user whether to execute it. `Y' or `y' will execute it, anything else will skip it. Note that you just need to type one character.
    -n  No execution: print what would happen, but don't do it.
    -q  Turn bare glob qualifiers off: now assumed by default, so this has no effect.
    -Q  Force bare glob qualifiers on. Don't turn this on unless you are actually using glob qualifiers in a pattern.
    -s  Symbolic, passed down to ln; only works with -L.
    -v  Verbose: print each command as it's being executed.
    -w  Pick out wildcard parts of the pattern, as described above, and implicitly add parentheses for referring to them.
    -W  Just like -w, with the addition of turning wildcards in the replacement pattern into sequential ${1} .. ${N} references.
    -C
    -L
    -M  Force cp, ln or mv, respectively, regardless of the name of the function.
    -p program
        Call program instead of cp, ln or mv. Whatever it does, it should at least understand the form `program -- oldname newname' where oldname and newname are filenames generated by zmv.
    -o optstring
        The optstring is split into words and passed down verbatim to the cp, ln or mv command called to perform the work. It should probably begin with a `-'.

    For more complete examples and other implementation details, see the zmv source file, usually located in one of the directories named in your fpath, or in Functions/Misc/zmv in the zsh distribution.

zrecompile
    See `Recompiling Functions' above.

zstyle+ context style value [ + subcontext style value ... ]
    This makes defining styles a bit simpler by using a single `+' as a special token that allows you to append a context name to the previously used context name. Like this:

        zstyle+ ':foo:bar' style1 value1 \
              + ':baz'     style2 value2 \
              + ':frob'    style3 value3

    This defines `style1' with `value1' for the context :foo:bar as usual, but it also defines `style2' with `value2' for the context :foo:bar:baz and `style3' with `value3' for :foo:bar:frob. Any subcontext may be the empty string to re-use the first context unchanged.

  Styles

insert-tab
    The zed function sets this style in context `:completion:zed:*' to turn off completion when TAB is typed at the beginning of a line. You may override this by setting your own value for this context and style.

pager
    The nslookup function looks up this style in the context `:nslookup' to determine the program used to display output that does not fit on a single screen.

prompt
rprompt
    The nslookup function looks up this style in the context `:nslookup' to set the prompt and the right-side prompt, respectively. The usual expansions for the PS1 and RPS1 parameters may be used (see zshmisc(1)).