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| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | Doc/Zsh/expn.yo | 87 |
2 files changed, 55 insertions, 38 deletions
diff --git a/ChangeLog b/ChangeLog index 6e6bd380a..b1172382f 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2001-07-25 Bart Schaefer <schaefer@zsh.org> + + * 15488: Doc/Zsh/expn.yo: More index entry cleanup. Reorder the + description section to look less as if it has two menus in info + and to add some cross-references. + 2001-07-25 Sven Wischnowsky <wischnow@zsh.org> * 15487: Completion/Base/Utility/_describe, Src/Zle/complete.c: diff --git a/Doc/Zsh/expn.yo b/Doc/Zsh/expn.yo index a4631f37b..52604cfd0 100644 --- a/Doc/Zsh/expn.yo +++ b/Doc/Zsh/expn.yo @@ -1,36 +1,44 @@ texinode(Expansion)(Parameters)(Prompt Expansion)(Top) chapter(Expansion) cindex(expansion) -sect(Description) -The types of expansions performed are - -startlist() -list(em(History Expansion)) -list(em(Alias Expansion)) -list(em(Process Substitution)) -list(em(Parameter Expansion)) -list(em(Command Substitution)) -list(em(Arithmetic Expansion)) -list(em(Brace Expansion)) -list(em(Filename Expansion)) -list(em(Filename Generation)) -endlist() - -Expansion is done in the above specified order in five steps. The -first is em(history expansion), which is only performed in -interactive shells. The next step is em(alias expansion), which is -done right before the command line is parsed. They are followed by -em(process substitution), em(parameter expansion), em(command -substitution), em(arithmetic expansion) and em(brace expansion) -which are performed in one step in left-to-right fashion. After -these expansions, all unquoted occurrences of the characters `tt(\)', -`tt(')' and `tt(")' are removed, and the result is subjected to -em(filename expansion) followed by em(filename generation). +ifnztexi(sect(Description)) +The following types of expansions are performed in the indicated order in +five steps: -If the tt(SH_FILE_EXPANSION) option is set, the order of expansion is modified -for compatibility with bf(sh) and bf(ksh). em(Filename expansion) -is performed immediately after em(alias expansion), +startitem() +item(em(History Expansion))( +This is performed only in interactive shells. +) +item(em(Alias Expansion))( +Aliases are expanded immediately before the command line is parsed as +explained +ifzman(under Aliasing in zmanref(zshmisc))\ +ifnzman(in noderef(Aliasing))\ +. +) +xitem(em(Process Substitution)) +xitem(em(Parameter Expansion)) +xitem(em(Command Substitution)) +xitem(em(Arithmetic Expansion)) +item(em(Brace Expansion))( +These five are performed in one step in left-to-right fashion. After +these expansions, all unquoted occurrences of the characters `tt(\)', +`tt(')' and `tt(")' are removed. +) +item(em(Filename Expansion))( +If the tt(SH_FILE_EXPANSION) option is set, the order of expansion is +modified for compatibility with bf(sh) and bf(ksh). In that case +em(filename expansion) is performed immediately after em(alias expansion), preceding the set of five expansions mentioned above. +) +cindex(globbing) +item(em(Filename Generation))( +This expansion, commonly referred to as bf(globbing), is always done last. +) +enditem() + +The following sections explain the types of expansion in detail. + startmenu() menu(History Expansion) menu(Process Substitution) @@ -192,8 +200,11 @@ tt(!?) expansion (possibly in an earlier command). Anything else results in an error, although the error may not be the most obvious one. texinode(Modifiers)()(Word Designators)(History Expansion) subsect(Modifiers) -cindex(modifiers, history) +cindex(modifiers) +cindex(colon modifiers) cindex(history modifiers) +cindex(globbing modifiers) +cindex(parameter modifiers) After the optional word designator, you can add a sequence of one or more of the following modifiers, each preceded by a `tt(:)'. These modifiers also work on the result @@ -312,7 +323,7 @@ tt(>) is selected then writing on this special file will provide input for var(list). If tt(<) is used, then the file passed as an argument will be connected to the output of the var(list) process. For example, -nofill(tt(paste <LPAR()cut -f1) var(file1)tt(RPAR() <LPAR()cut -f3) var(file2)tt(RPAR() | +example(tt(paste <LPAR()cut -f1) var(file1)tt(RPAR() <LPAR()cut -f3) var(file2)tt(RPAR() | tee >LPAR())var(process1)tt(RPAR() >LPAR())var(process2)tt(RPAR() >/dev/null)) cuts fields 1 and 3 from the files var(file1) and var(file2) respectively, @@ -334,7 +345,8 @@ information using a pipe, so that programmes that expect to lseek Also note that the previous example can be more compactly and efficiently written (provided the tt(MULTIOS) option is set) as: -nofill(tt(paste <LPAR()cut -f1) var(file1)tt(RPAR() <LPAR()cut -f3) var(file2)tt(RPAR() > >LPAR())var(process1)tt(RPAR() > >LPAR())var(process2)tt(RPAR())) +example(tt(paste <LPAR()cut -f1) var(file1)tt(RPAR() <LPAR()cut -f3) var(file2)tt(RPAR()) ifzman(\ +)tt(> >LPAR())var(process1)tt(RPAR() > >LPAR())var(process2)tt(RPAR())) The shell uses pipes instead of FIFOs to implement the latter two process substitutions in the above example. @@ -365,7 +377,7 @@ the pattern is the same as that used for filename generation; see noderef(Filename Generation). Note that these patterns, along with the replacement text of any substitutions, are themselves subject to parameter expansion, command substitution, and arithmetic expansion. -In addition to the following operations, the file modifiers described in +In addition to the following operations, the colon modifiers described in noderef(Modifiers) in noderef(History Expansion) can be applied: for example, tt(${i:s/foo/bar/}) performs string substitution on the expansion of parameter tt($i). @@ -501,7 +513,7 @@ Note that `tt(^)', `tt(=)', and `tt(~)', below, must appear to the left of `tt(#)' when these forms are combined. ) item(tt(${^)var(spec)tt(}))( -pindex(RC_EXPAND_PARAM, use of) +pindex(RC_EXPAND_PARAM, toggle) cindex(array expansion style, rc) cindex(rc, array expansion style) Turn on the tt(RC_EXPAND_PARAM) option for the @@ -522,9 +534,9 @@ tt($var[)var(N)tt(]) may themselves be split into different list elements. ) item(tt(${=)var(spec)tt(}))( -pindex(SH_WORD_SPLIT, use of) -cindex(field splitting, sh style) -cindex(sh, field splitting style) +pindex(SH_WORD_SPLIT, toggle) +cindex(field splitting, sh style, parameter) +cindex(sh, field splitting style, parameter) Perform word splitting using the rules for tt(SH_WORD_SPLIT) during the evaluation of var(spec), but regardless of whether the parameter appears in double quotes; if the `tt(=)' is doubled, turn it off. @@ -538,7 +550,7 @@ of var(spec) em(before) the assignment to var(name) is performed. This affects the result of array assignments with the tt(A) flag. ) item(tt(${~)var(spec)tt(}))( -pindex(GLOB_SUBST) +pindex(GLOB_SUBST, toggle) Turn on the tt(GLOB_SUBST) option for the evaluation of var(spec); if the `tt(~)' is doubled, turn it off. When this option is set, the string resulting from the expansion will be interpreted as a @@ -1102,7 +1114,6 @@ first `tt(=)' also inhibits this. texinode(Filename Generation)()(Filename Expansion)(Expansion) sect(Filename Generation) cindex(filename generation) -cindex(globbing) If a word contains an unquoted instance of one of the characters `tt(*)', `tt(LPAR())', `tt(|)', `tt(<)', `tt([)', or `tt(?)', it is regarded as a pattern for filename generation, unless the tt(GLOB) option is unset. |