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Diffstat (limited to 'NEWS')
| -rw-r--r-- | NEWS | 606 |
1 files changed, 265 insertions, 341 deletions
diff --git a/NEWS b/NEWS index 629836466..1a69494fb 100644 --- a/NEWS +++ b/NEWS @@ -4,357 +4,281 @@ CHANGES FROM PREVIOUS VERSIONS OF ZSH Note also the list of incompatibilities in the README file. -Changes since 4.3.15 --------------------- - -The option HASH_EXECUTABLES_ONLY has been added. When this is set, -directories in the command path will be checked for executables before -they are added to the command table (hash); otherwise, all files in the -directory are added. The effect of this option was present in 4.3.15, -which could cause significant delays when hashing on systems with -network directories in the path. - -Changes since 4.3.12 --------------------- - -There are no significant feature changes to the shell itself, although -many bug fixes and improvements to functions. - -Changes since 4.3.11 --------------------- - -The zsh/parameter module has a new readonly associative array -$usergroups whose keys are the names of system groups of which the -current user is a member and whose values are the corresponding -group identifiers. - -The region_highlight array, which controls highlighting of the -command line from zle widgets, is now updated dynamically as -the command line is edited. - -In POSIX emulation ("emulate sh") the shell is more accurate about -when it should or should not exit on errors. - -The ${NAME:OFFSET:LENGTH} syntax now supports negative LENGTH, which -counts back from the end of the string. - -The (g:opts:) flag in parameter expansion processes escape sequences like -the echo and print builtins. opts can be any combination of o, e and c. -With e, acts like print rather than echo except for octal escapes which -are controlled separately by the o option. With c, interpret control -sequences like "^X" as bindkey does. Regardless of the opts, \c is not -interpreted. - -Changes between versions 4.3.10 and 4.3.11 ------------------------------------------- - -When the shell is invoked with the base name of a script, for example as -`zsh scriptname', previous versions of zsh have used the name directly, -whereas other shells use the value of $PATH to find the script. The -option PATH_SCRIPT has been added to provide the alternative behaviour. -This is turned on where appropriate in compatibility modes. - -Parameters, globbing, etc. --+-+-+-+-+-+-+-+-+-+-+-+-+ - -Parameter expansion has been enhanced to provide the ${NAME:OFFSET} and -${NAME:OFFSET:LENGTH} syntax for substrings and subarrays present in -several other shells. OFFSET always uses zero-based indexing. The only -clash with existing zsh syntax occurs if OFFSET begins with an -alphabetic character or `&', which is not likely. - -The (D) flag in parameter expansion abbreviates directories in the -substituted value. The (q-) flag does minimal shell quotation of arguments -for maximum human readability of the result. - -The (Z) flag in parameter expansion is an enhanced version of the (z) -flag that takes an argument indicating how the string to be split -is treated. (Z:c:) parses comments as strings; (Z:C:) parses comments -and strips them; (Z:n:) treats newlines as ordinary whitespace: (z) -has always treated unquoted newlines as shell delimiters and turned them -into semicolons, though this was not previously documented. - -Numeric expansion with braces has been extended so that a step may be -given, as in {3..9..2}. The step may be negative as may the start and -end of the range (this is also new). - -The glob qualifier P can be used to add a separate word before each -match. For example, *(P:-f:) produces the command line -`-f file1 -f file2 ...'. - -Regular expression matches now use the same variables for storing matched -components as shell pattern matching. The function system now provides the -function regexp-replace for replacing text using regular expressions. The -zle widget functions replace-string, replace-string-again, if defined with -regex in the name (e.g. "zle -N replace-regexp replace-string"), perform -regular expression matches. In replacement text \& and \1 have the -standard meaning. - -Line editor and completion --+-+-+-+-+-+-+-+-+-+-+-+-+ - -The completion system now has a style path-completion. Setting this to -false inhibits completion of paths before the current path component, -e.g. /u/b/z no longer completes to /usr/bin/zsh. This is useful on systems -where this form of completion is pathologically slow due to network -performance. - -With the MULTIBYTE option, the line editor now highlights bytes in the -input that are not part of a valid character in the current locale in hex -as <XX> for hex digits X; highlighting is controlled by the "special" -keyword in the zle_highlight array. These can be distinguished from -unprintable Unicode characters which also use "special" highlighting as the -latter are always two or four bytes long, e.g. <XXXX>, <XXXXXXXX>. - -zle_highlight also controls highlighting of a removable completion -suffix, e.g. the "/" automatically appended to directories. This uses -the keyword "suffix". - -The line editor now sets the variable ZLE_LINE_ABORTED if there is -an error when editing the line. The following code can be used -to create a bindable editor widget to restore the aborted line: - recover-line() { LBUFFER=$ZLE_LINE_ABORTED RBUFFER=; } - zle -N recover-line -and then either bind recover-line to a key sequence or use -`M-x recover-line <RET>'. - -The parameter ZLE_STATE, available in user-defined line editor widgets, -gives information on the state of the line editor. Currently this is -whether the line editor is in insert or overwrite mode. - -Miscellaneous options --+-+-+-+-+-+-+-+-+-+- - -The new shell option HIST_LEX_WORDS causes history lines read in from -a file to be split in the same way as normal shell lines, instead of -simply on whitespace. It's an option as although the result is more -accurate it can take a long time when the history size is large. - -The shell option MONITOR can be set in non-interactive shells, and also in -subshells (as created by surrounding commands with parentheses), turning on -job control for that subshell. The initial behaviour of a subshell is -still to turn job control off, however if the new POSIX_JOBS option is set -MONITOR remains active in subshells. - -The new shell option POSIX_CD, active in emulations of POSIX-based shells, -makes the cd builtin POSIX-compatible. - -The POSIX_JOBS option already referred to has various other -compatibility enchancements. - -The new shell option POSIX_STRINGS makes a null character in $'...' -expansion terminate the string, as is already the case in bash. This is -not particularly useful behaviour but may become a POSIX requirement. - -The new shell option POSIX_TRAPS causes the EXIT trap to behave in the same -way as in other shells, i.e. it is only run when the shell exits. - -The new shell option SOURCE_TRACE causes the shell to report files -containing shell code that the shell executes directly, i.e. startup files -or files run with the `source' or `.' builtins. - -The shell option SUN_KEYBOARD_HACK has been supplemented by a more general -mechanism: the KEYBOARD_HACK variable defines the character to be ignored. - -Add-on modules and function --+-+-+-+-+-+-+-+-+-+-+-+-+- +Changes between 4.2 and 5.0 +--------------------------- -The module zsh/system has a new "zsystem" builtin whose subcommands perform -system level tasks. Currently "zsystem flock" performs advisory file -locking (for aficionados, this uses the fcntl() system call so works over -the network on Linux). This is a particularly convenient way of locking -files for the length of a subshell. "zsystem supports flock" provides a -test for this feature. +The following changes first appeared in the 4.3 series of releases; +see also the file Etc/NEWS-4.3. -There is now a function system for recording and restoring recently -entered directories in a persistent fashion, with support in completion -and (if explicitly installed) dynamic directory expansion. See the -entry for cdr in the zshcontrib manual page. +Here is a summary of the most significant changes: +- Multibyte characters strings are supported throughout the shell. + Various options, editor features, and expansion flags have been + added to aid in using them. -Changes between versions 4.3.9 and 4.3.10 ------------------------------------------ +- The following new options have appeared: COMBINING_CHARS, + DEBUG_BEFORE_CMD, HASH_EXECUTABLES_ONLY, HIST_FCNTL_LOCK, + HIST_LEX_WORDS, HIST_SAVE_BY_COPY, MULTIBYTE, NO_MULTI_FUNCDEF, + PATH_SCRIPT, POSIX_ALIASES, POSIX_CD, POSIX_JOBS, POSIX_STRINGS, + POSIX_TRAPS, PROMPT_SP, SOURCE_TRACE. + +- Highlighting and colouring of the command line is supported. + +- Job control is supported in non-interactive shells and subshells. + +- The zshroadmap manual page provides a slightly more helpful + introduction to the shell manual than was available hitherto. + +Expansion (parameters, globbing, etc.) and redirection +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +- The character group tests [[:IDENT:]], [[:IFS:]], [[:IFSSPACE:]], + [[:WORD:]] in patterns allow testing if a character can be + part of an identifier, is an IFS character, is an IFS whitespace + character, or is considered part of the word using the line editor's + logic based on the shell variable WORDCHARS. + +- In extended globbing, "(#cN,M)" means "match the preceding group + at least N but no more than M times". + +- The glob qualifier P can be used with an argument to add an extra + word before each glob match. + +- The syntax ~[...] provides dynamic directory naming by means + of the shell function zsh_directory_name or associated hook functions. + This is useful for expanding paths with many variable components as + commonly found in software development. + +- Parameter expansion has the ${NAME:OFFSET} and ${NAME:OFFSET:LENGTH} + syntax for compatibility with other shells (and zero-based indexing + is used to enhance compatibility). LENGTH may be negative to count + from the end. + +- The parameter expansion flag (D) abbreviates directories in parameters + using the familiary ~ form. + +- The parameter expansion flag (g) can take delimited arguments o, e and + c to provide echo- and print-style expansion: (g::) provides basic + echo-style expansion; (g:e:) provides the extended capabilities of + print; (g:o:) provides octal escapes without a leading zero; (g:c:) + additional expands "^c" style control characters as for bindkey. + Options may be combined, e.g. (g:eoc:). + +- The parameter expansion flag (q-) picks the most minimal way of + quoting the parameter words, to make the result as readable as possible. + +- The parameter expansion flag (Z), a variant of (z), takes arguments + describing how to split a variable using shell syntax: (Z:c:) parses + comments as strings (the default is not to treat comment characters + specially); (Z:C:) parses comments and strips them; (Z:n:) treats + newlines as ordinary whitespace (the default is to turn unquoted + newlines into semicolons; this is now documented). + +- The parameter subscript flag (e) forces the argument to be treated + as a string, never a pattern, e.g. ${array[(ie)*]} looks for the + index of the array element containing the literal string "*". + +- Numeric expansions can have a positive or negative step + e.g. "{3..9..2}". Negative start and end of ranges are also now + supported. + +- =(<<<...) is optimised to eliminate the need for an external process. + It writes the given string to a file and substitutes the name on the + command line. + +- The redirection operations "{myfd}>file" and "{myfd}>&-" open and + close a new file descriptor (at least 10) contained in the shell + variable myfd, which can be written to with ">&$myfd". This allows + arbitrary file descriptors rather than the explicit range 0 to 9. + +- New prompt escapes: + %x and %I show source file and line number, usefil + in $PS4 (the existing %N and %i show names and lines in the execution + environment rather than the source file). + %F, %K, %f, %k allow colouring of prompts both using ANSI colour names + and values supported by individual terminal emulators. + +Builtins and shell functions +-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +- Directory changing builtins take an option -q to suppress side + effects such as printing directories or calling the chpwd hook functions. + +- Various enhancements have been made to traps: + - The option DEBUG_BEFORE_CMD is on by default, so DEBUG traps + can be used to debug code about to be run + - $ZSH_DEBUG_CMD in such a trap gives the code to be run + - "setopt ERR_EXIT" in a DEBUG trap causes the code not to be executed + +- The "fc" builtin is now more useful non-interactively. + +Shell variables (parameters) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +- New variables: + CORRECT_IGNORE can be set to a pattern to be ignored in spelling correction. + KEYBOARD_HACK defines characters to be ignored if typed unmatched at + the end of the line (an extension of the SUN_KEYBOARD_HACK option). + ZSH_PATCHLEVEL provides a unique indication of the code compiled to + make the shell even between releases. + ZSH_SUBSHELL indicates the subshell live, incremented once per fork, at + which the code is being run. + +Options +-+-+-+- + +- New options: + COMBINING_CHARS: assume that the terminal displays combining + characters correctly. The shell cannot determine this by itself, + hence the option. This is highly recommended for MacOS X where + file names are stored with accented characters split into basic + and combining characters. + DEBUG_BEFORE_CMD (on by default): execute debug traps before the + code they refer to. This is a change of the default behaviour + as the new behaviour is much more useful. + HASH_EXECUTABLES_ONLY: don't insert non-executable files into the + command hash used e.g. by completion. This may be very slow + on network paths. + HIST_FCNTL_LOCK: Use the system's file locking mechanism instead + of an ad-hoc mechanism for locking history files. + HIST_LEX_WORDS: Perform lexical analysis on history lines read from + files, so the words are more accurately determined. May be very slow. + HIST_SAVE_BY_COPY (on by default): if unset, write a history file in + place by truncating the old one. Only needs to be turned off in + special circumstances. + MULTIBYTE (on by default if available): both variables and editor + command lines are treated as sequences of multibyte characters + rather than raw bytes depending on the locale. May be turned off + within functions to perform bytewise operations. + MULTI_FUNCDEF (on by default): "foo bar () { ... }" defines two + functions. This is often found to be confusing and bug-prone. + PATH_SCRIPT: search the path for a script specified as the first + argument to the shell on invocation. + POSIX_ALIASES: reserved words are not candidates for alias expansion. + POSIX_CD: make directory changing more POSIX-compatible. + POSIX_JOBS: make job control more POSIX compliant. + POSIX_STRINGS: $'...\0...' always processes \0 as a NULL, but if the + option is set the remainder of the string is ignored. + POSIX_TRAPS: EXIT traps are not executed on return from shell functions. + PROMPT_SP: improves display of lines not ending with newlines when + PROMPT_CR is in effect. + SOURCE_TRACE: print information as files are executed with ".", + "source", or as startup or shutdown files. + +Line editor +-+-+-+-+-+- + +- Supports multibyte characters, including characters wider than one + screen cell and (with the COMBINING_CHARS option) combining characters. + +- New builtin widgets: + arguments-base: allow non-decimal numeric arguments + history-incremental-pattern-search-{backward,forward}: support + patterns in incremental searches. + +- New special variables: + region_highlight allows arbitrary highlighting of parts of the + command line; it is maintained dynamically. + UNDO_CHANGE_NO gives a unique record of the current change state of + the command line, for undoing back to a particular point using + the undo widget. + zle_highlight provides master control of highlighting for special + modes, e.g. unprintable characters. + ZLE_LINE_ABORTED records an editor line that was aborted by an error + or C-g. It can be used to recover aborted lines. + ZLE_STATE give miscellaneous information, currently whether the line + editor is in insert or overwrite mode. + +- The undo widget takes an argument, a previous value of $UNDO_CHANGE_NO. + +Completion +-+-+-+-+-+ + +- Many new and enhanced completion functions + +- New styles: + accept-exact-dirs: suppress path expansion of directory components + that already exist, speeding up completion significantly on slow + network directories. + path-completion: can be used to suppress directory components before + the current one completely, so e.g. /u/b<TAB> only completes after the + "b", not the "u". + +- New special variables: + ZLE_REMOVE_SUFFIX_CHARS, ZLE_SPACE_SUFFIX_CHARS provide enhanced + flexibility over suffix removal. + +- Matching control, typically handling with the matcher-list style, + supports named character ranges, such as [:upper:], wherever + ranges were allowed, for example 'm:{[:upper:]}={[:lower:]}'. + However, matching control does not yet handle multibyte characters + properly, so this is currently limited to ASCII. + +Syntax and compatibility +-+-+-+-+-+-+-+-+-+-+-+-+ + +- Substitutions of the form ${var:-"$@"} and ${var:+"$@"} now behave + much more like other shells when appropriate (e.g. with the + SH_WORD_SPLIT option). + +- Assignments within variable substitutions, such as ${var=value}, + are also more compatible with other shells where appropriate. + +- The emulate command can now be passed an expression to be evaluated + in a "sticky" emulation, so that functions defined there always + behave in the appropriate emulation. + +- "emulate sh" and similar modes have improved compatibility with + respect to deciding whether the shell should exit on errors. + +- Signals now accept SIG as part of the name. + +Modules +-+-+-+- + +- Modules now present "features", specific builtins (b:), parameters + (p:), conditions (c:) and math functions (f:), allowing more control + over what is imported from a module. + +- The zsh/curses module provides access to the "curses" screen + manipulation package. + +- The zsh/datetime module has a calendar utility, although it is not + as robust as standalone calendar utilities. + +- The zsh/newuser module and associated functions has facilities for + setting up startup files for a first-time user. + +- The zsh/parameter module contains some new arrays to aid in tracing + of the shell's call stack: $funcsourcetrace and $funcfiletrace. + +- The zsh/parameter module provides $usergroups, an associative arrays + whose keys are the names of groups the current user belongs to, with + the group identifier as the corresponding value. + +- The zsh/system module has a zsystem builtin which provides file + locking and also a forward-compatible means for testing subcommands + supported. -The command "emulate <mode> -c ..." evaluates an expression in a given -emulation. The emulation is sticky for functions defined within the -expression. - -The variable CORRECT_IGNORE gives a pattern that can be ignored -in spelling correction. CORRECT_IGNORE='_*' ignores completion functions. - -The option POSIX_ALIASES improves compatibility of aliases with other -shells. - -The variable ZSH_PATCHLEVEL can be used to test for unreleased versions of -the shell; it is present but less useful in released versions. - -The variables ZLE_REMOVE_SUFFIX_CHARS and ZLE_SPACE_SUFFIX_CHARS allow more -control over the way automatically removed suffixes are treated in -completion. +Internal improvements +-+-+-+-+-+-+-+-+-+-+- -Major changes between versions 4.3.6 and 4.3.9 ----------------------------------------------- +- High resolution timestamps are used internally for certain + comparisons when available. -The option COMBINING_CHARS has been added. When it is set, the -line editor assumes the terminal is capable of displaying zero-width -combining characters (typically accents) correctly as modifications -to the base character, and will act accordingly. Note it is not set -by default owing to vagaries of terminals. The system is reported -to work on MacOS, where this is particularly important as accented -characters in file names are stored in their decomposed form (i.e. -with base and combining characters). - -The option HIST_FCNTL_LOCK has been added to provide locking of history -files using the system call fcntl(). On recent NFS implementations this -may provide better reliability. - -The syntax ~[...] provides a dynamic form of directory naming, -supplementing the existing static ~name syntax. A user-defined shell -function, zsh_directory_name, is used to handle both expansion of names to -directories and contraction of directories to names. - -Patterns can now be used in incremental searches with the new widgets -history-incremental-pattern-search-backward and -history-incremental-pattern-search-forward. These are not bound to -keys by default. - -Highlighting and colouring of sections of the command line is now -supported, controlled by the array parameter zle_highlight and the ZLE -special parameter region_highlight. - -Colouring of prompts is now supported within the shell by prompt -escapes. The prompt theme system has been updated. - -Various changes have been added to make debugging of shell code easier: - - As noted in README, the option DEBUG_BEFORE_CMD is now set by default. - - In DEBUG traps, $ZSH_DEBUG_CMD gives the code for which the trap is - called as a string. - - "setopt ERR_EXIT" in a DEBUG trap causes the code not to be executed. - - $ZSH_SUBSHELL indicates the subshell level at which code is being - executed. - - The zsh/parameter module has various additional arrays similar to - the existing $funcstack and $functrace, namely $funcsourcetrace - and $funcfiletrace. The consistency and informativeness of - the output of all these arrays has been improved. - - Prompt escapes %x and %I show the source file and line number in - debug prompts (compare %N and %i which show names and line numbers - in the execution environment). - - The option NO_MULTI_FUNCDEF can turn off multiple definition of - functions at once, a rarely used feature that can cause problems - with misplaced "()". - - The "fc" builtin has been enhanced to make non-interactive use possible - and output consistent when the history is manipulated with "print -s". - -The completion style accept-exact-dirs has been added. When true, this -suppresses attempts to complete non-final directory segments of a filename -path when the directory exists. (For example, /home/pws/src/zsh/<TAB> -discovers that /home/pws/src/zsh exists and leaves the directory component -alone, while /h/p/s/z/<TAB> completes to /home/pws/src/zsh/... as before.) -This should improve completion behaviour noticeably in special cases, such -as remote paths under Cygwin. - -Major changes between versions 4.3.5 and 4.3.6 ----------------------------------------------- +Add-on functions +-+-+-+-+-+-+-+-+ -cd, chdir, pushd and popd now take a -q option to suppress side effects -including printing the directory stack (for pushd and popd) and executing -the chpwd hook functions (for all four). +- The VCS_Info system provides a way of keeping track of the state + of numerous version control systems within the shell. -The parameter subscript (e) flag now forces the argument to be treated -as a string where it would previously have been treated as a pattern, -for example ${array[(ie)*]} substitutes the index of the element whose -value is "*". - -Major changes between versions 4.3.4 and 4.3.5 ----------------------------------------------- +- cdr etc.: change to a directory from a list that persists between + shell instances, with completion support. -- The new extended globbing flag (#cN,M) behaves similarly to the extended - regular expression syntax {N,M}. - -- The zsh/datetime module has been enhanced and a calendar function - system has been added along the lines of (but much enhanced from) - the traditional Unix "calendar" utility. This is still under - development. See the zshcalsys manual. (The calendar functions - were in 4.3.4 but were not listed in this file. There have been - significant enhancements since 4.3.4.) - -- A new module zsh/curses provides a builtin zcurses for access to - to the curses screen manipulation package. See the entry for zsh/curses - in the zshmodules manual. - -- The module system has been enhanced to support the notion of "features" - that give more control over which builtins, parameters, conditions - and math functions are loaded from a module. In particular, - "zmodload -F zsh/stat b:zstat" makes the builtin previously called - "stat" available as "zstat" (only) to avoid clashes with a system - command named "stat". - -Major changes between versions 4.2 and 4.3.4 --------------------------------------------- - -- There is support for multibyte character sets. This is now reasonably - close to complete, although Unicode combining characters don't work - properly. See Multibyte Character Support in INSTALL. - -- The shell can now run an installation function for a new user - (a user with no .zshrc, .zshenv, .zprofile or .zlogin file) without - any additional setting up by the administrator. See "THE ZSH/NEWUSER - MODULE" in the zshmodules manual page. - -- The manual now has a Roadmap section (manual page zshroadmap) to - give new users an indication of the most interesting parts of the - manual. - -- New option PROMPT_SP (on by default): works around the problem that the - line editor can overwrite output with no newline at the end. See the - zshoptions manual page. - -- New option HIST_SAVE_BY_COPY (on by default): history is saved by - copying and renaming instead of directly overwriting. See the - zshoptions manual page. - -- New redirection syntax e.g. {myfd}>file opens a new file descriptor - and stores the number in $myfd, so that >&$myfd will work. Chosen - not to break existing code (and to be compatible with proposals for the - Korn shell). See the section REDIRECTION in the zshmisc manual page. - -- Substitutions of the form ${var:-"$@"}, ${var:+"$@"} and similar where - word-splitting is applied to the text after the :- or :+ (in particular, - where the SH_WORD_SPLIT option is in effect for compatibility) now - behave as in other Bourne- and POSIX-compatible shells when in the - appropriate emulation mode. - -- New Posix-style zsh-specific tests [[:IDENT:]], [[:IFS:]], - [[:IFSSPACE:]], [[:WORD:]] test if character can appear in identifier, - is an IFS character, is an IFS whitespace character, or is considered - as part of a word (is alphanumeric or appears in $WORDCHARS). These - works correctly on multibyte characters if the appropriate support - is present. See the section FILENAME GENERATION in the zshexpn - manual page. - -- Time comparisons on files when sorting or using test operators will - use high-resolution timestamps when available. This gives a - resolution of a nanosecond instead of a second. - -- The idiom =(<<<...) is optimised so that the shell internally turns - the ... into the contents of a file whose name is then substituted. - The syntax has always been usable by means of the NULLCMD feature, - but previously it generated an intermediate process; it has now - been rewritten along the same lines as the optimisation for $(<...) - that inserts a file into the command line without the use of an - external programme. - -- Supplied functions catch and throw provide limited support for - exception handling using the `{ ... } always { ... }' syntax. - See the section EXCEPTION HANDLING in the zshcontrib manual page. - -- Signals now accept the SIG as part of the name for compatibility with - other shells. - -- Editor function argument-base allows non-decimal arguments for - editor widgets. See the entry in the zshzle manual page. - -- As always, there are many enhancements to completion functions. +- regexp-replace replaces text in variables using regular expressions; + it may be used by zle function widgets based on the functions + replace-string and replace-string-again to provide regular expression + replacements in the line editor. Changes in 4.2 since version 4.2.0 ---------------------------------- |