diff options
Diffstat (limited to 'README')
| -rw-r--r-- | README | 110 |
1 files changed, 106 insertions, 4 deletions
@@ -5,10 +5,10 @@ THE Z SHELL (ZSH) Version ------- -This is version 5.2 of the shell. This is a stable release. There are -a few visible improvements since 5.1.1 as well as many bugfixes. Note +This is version 5.3 of the shell. This is a stable release. There are +a few visible improvements since 5.2 as well as many bugfixes. Note in particular the changs highlighted under "Incompatibilites -between 5.1 and 5.2" below. See NEWS for more information. +between 5.2 and 5.3" below. See NEWS for more information. Installing Zsh -------------- @@ -32,7 +32,7 @@ details, see the documentation. Incompatibilities between 5.2 and 5.3 ------------------------------------- -In character classes delimited by "[" and "]" within patterns, whether +1) In character classes delimited by "[" and "]" within patterns, whether used for filename generation (globbing) or other forms of pattern matching, it used not to be possible to quote "-" when used for a range, or "^" and "!" when used for negating a character set. The characters can @@ -58,6 +58,108 @@ The "~" causes the "-" character to be active. In sh emulation the "~" is unncessary in this example and double quotes must be used to suppress the range behaviour of the "-". +2) The first argument to 'repeat' is now evaluated as an arithmetic +expression. It was always documented to be an arithmetic expression, but +until now the decimal integer at the start of the value was used and the +remainder of the value discarded. This could lead to different behaviour +if the argument contains non-numeric characters, or if the argument has +leading zeroes and the OCTAL_ZEROES option is set. + +3) For some time the shell has had a POSIX_TRAPS option which determines +whether the EXIT trap has POSIX behaviour (the trap is only run at shell +exit) or traditional zsh behaviour (the trap is run once and discarded +when the enclosing fuction or shell exits, whichever happens first). +The use of this option has now been made "sticky" on the EXIT trap --- +in other words, the setting of the option at the point where the trap is +set now determines whether the trap has POSIX or traditional zsh +behaviour. This means that changing the option after the trap was set +no longer has any effect. + +Other aspects of EXIT trap handling have not changed --- there is still +only one EXIT trap at any point in a programme, so it is not generally +useful to combine POSIX and non-POSIX behaviour in the same script. + +4) There was an undocumented feature dating from the early days of zsh +that glob qualifiers consisting only of the digits 0 to 7 were treated +as an octal file mode to "and" with the modes of files being tested. +This has been removed in order to be more sensitive to syntax errors. +The "f" qualifier has for many years been the documented way of testing +file modes; it allows the "and" test ("*(f+1)" is the documented +equivalent of "*(1)") as well as many other forms. + +5) The completion helper function _arguments now escapes both backslashes +and colons in the values of option arguments when populating the $opt_args +associative array. Previously, colons were escaped with a backslash but +backslashes were not themselves escaped with a backslash, which lead to +ambiguity: '-x foo\:bar' (one argument with a backslashed colon) and +'-x foo\\ bar' (two arguments, and the first one ends in a backslash) would +both set $opt_args[-x] to the same value. This example assumes the -x +option's spec declared two arguments, as in: + _arguments : -x:foo:${action}:bar:$action + +For the more common case of non-repeatable options that take a single +argument, completion functions now have to unescape not only colons but +also backslashes when obtaining the option's argument from $opt_args. + +6) Previously, if the function command_not_found_handler was run +in place of a command-not-found error, and the function returned +non-zero status, zsh set the status to 127 and printed an error message +anyway. Now, the status from the handler is retained and no additional +message is printed. The main reasons for this change are that it was not +possible to return a non-zero status to the parent shell from a command +executed as a replacement, and the new implementation is more consistent +with other shells. + +7) The output of "typeset -p" (and synonyms) now takes into account the +function scope and export state of each parameter. Exported parameters +are output as "export" commands unless the parameter is also local, and +other parameters not local to the scope are output with the "-g" option. +Previously, only "typeset" commands were output, never using "-g". + +8) At spelling-correction prompt ($SPROMPT), where the choices offered are +[nyae], previously <Enter> would be accepted to mean [N] and <Space> and +<Tab> would be accepted to mean [Y]. Now <Space> and <Tab> are invalid +choices: typing either of them remains at the prompt. + +9) The $ary[i,j] subscript syntax to take a slice of an array behaves +differently when both i and j are larger than the number of elements in +the array. When i == j, such a slice always yields an empty array, and +when i < j it always yields an array of one empty string element. The +following example illustrates how this differs from past versions. + + nargs() { print $# } + a=(one two) + for i in 1 2 3 4; do + for j in 1 2 3 4 5; do + print -n "$i $j => " + nargs "${(@)a[i,j]}" + done + done + + 5.2 | 5.3 ** + ----------+---------- + 1 1 => 1 | 1 1 => 1 + 1 2 => 2 | 1 2 => 2 + 1 3 => 2 | 1 3 => 2 + 1 4 => 2 | 1 4 => 2 + 1 5 => 2 | 1 5 => 2 + 2 1 => 0 | 2 1 => 0 + 2 2 => 1 | 2 2 => 1 + 2 3 => 1 | 2 3 => 1 + 2 4 => 1 | 2 4 => 1 + 2 5 => 1 | 2 5 => 1 + 3 1 => 0 | 3 1 => 0 + 3 2 => 0 | 3 2 => 0 + 3 3 => 0 | 3 3 => 0 + 3 4 => 0 | 3 4 => 1 ** + 3 5 => 0 | 3 5 => 1 ** + 4 1 => 0 | 4 1 => 0 + 4 2 => 0 | 4 2 => 0 + 4 3 => 0 | 4 3 => 0 + 4 4 => 1 | 4 4 => 0 ** + 4 5 => 1 | 4 5 => 1 + + Incompatibilities between 5.0.8 and 5.2 --------------------------------------- |