From f297132cf0efe7da7c302a99e2fd9e44d1ddc64e Mon Sep 17 00:00:00 2001 From: Daniel Shahaf Date: Thu, 28 May 2020 20:30:49 +0000 Subject: 45932: FAQ (3.1): Update ksh compatibility answer for reserved word typeset. --- ChangeLog | 3 +++ Etc/FAQ.yo | 28 +++++++++++++++++++--------- 2 files changed, 22 insertions(+), 9 deletions(-) diff --git a/ChangeLog b/ChangeLog index dae78f74c..9a421e418 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,8 @@ 2020-06-07 Daniel Shahaf + * 45932: Etc/FAQ.yo: FAQ (3.1): Update ksh compatibility answer + for reserved word typeset. + * 45933: Etc/FAQ.yo: FAQ: Add "Why does my bash script report an error when I run it under zsh?". diff --git a/Etc/FAQ.yo b/Etc/FAQ.yo index c3b365b69..e4197a069 100644 --- a/Etc/FAQ.yo +++ b/Etc/FAQ.yo @@ -988,7 +988,7 @@ label(31) been automatic word splitting in scalars, which is a sort of uncontrollable poor man's array. - Note that this happens regardless of the value of the internal field + Note that word splitting happens regardless of the value of the internal field separator, tt($IFS); in other words, with mytt(IFS=:; foo=a:b; args $foo) you get the answer 1. @@ -1020,22 +1020,32 @@ label(31) or (entirely equivalent) when mytt(emulate ksh) or mytt(emulate sh) is in effect. - There is one other effect of word splitting which differs between ksh + There used to be another effect of word splitting which differed between ksh and zsh. In ksh, the builtin commands that declare parameters such as tt(typeset) and tt(export) force word-splitting not to take place after on an assignment argument: verb( typeset param=`echo foo bar` ) - in ksh will create a parameter with value mytt(foo bar), but in zsh will + in ksh will create a parameter with value mytt(foo bar). + + zsh used to create a parameter tt(param) with value tt(foo) and a parameter tt(bar) - whose value is empty. Contrast this with a normal assignment (no + whose value was empty. Contrast this with a normal assignment (no tt(typeset) or other command in front), which never causes a word split - unless you have tt(GLOB_ASSIGN) set. From zsh version 4.0.2 the option - tt(KSH_TYPESET), set automatically in compatibility mode, fixes this - problem. Note that in bash this behaviour occurs with all arguments that - look like assignments, whatever the command name; to get this behaviour - in zsh you have to set the option tt(MAGIC_EQUAL_SUBST). + unless you have tt(GLOB_ASSIGN) set. + + zsh version 4.0.2 and newer creates a single parameter with value + mytt(foo bar), like ksh does, when the option tt(KSH_TYPESET) is set. + This option gets set automatically when in ksh compatibility mode. + + zsh 5.1 and newer create a single parameter with value mytt(foo bar) by + default, in both compatibility and native modes. The older behaviour + can be obtained with mytt(disable -r typeset). + + If the options mytt(MAGIC_EQUAL_SUBST) and mytt(KSH_TYPESET) are both + set, arguments that look like assignments will not undergo word + splitting, whatever the command name. sect(In which startup file do I put...?) -- cgit 1.4.1