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| author | Jim Porter <jporterbugs@gmail.com> | 2022-08-08 21:24:27 -0700 |
|---|---|---|
| committer | Jim Porter <jporterbugs@gmail.com> | 2022-08-12 22:07:13 -0700 |
| commit | 9d4fa4ed4b1f2b081e8ed14cbe16d9ec4b993988 (patch) | |
| tree | 2831401200113ed59e4ebb1385f99ca612c0c73c /doc/misc/eshell.texi | |
| parent | 30320d9420b2850341e94fa1b10476344bfa9589 (diff) | |
| download | emacs-9d4fa4ed4b1f2b081e8ed14cbe16d9ec4b993988.tar.gz | |
Allow using dollar expansions in Eshell conditionals
* lisp/eshell/esh-cmd.el (eshell-structure-basic-command): Forms
beginning with 'eshell-escape-arg' are "data-wise".
* test/lisp/eshell/esh-cmd-tests.el (esh-cmd-test/while-loop)
(esh-cmd-test/until-loop, esh-cmd-test/if-statement)
(esh-cmd-test/if-else-statement, esh-cmd-test/unless-statement)
(esh-cmd-test/unless-else-statement): Use variable interpolation.
(esh-cmd-test/while-loop-ext-cmd, esh-cmd-test/until-loop-ext-cmd)
(esh-cmd-test/if-else-statement-ext-cmd)
(esh-cmd-test/unless-else-statement-ext-cmd): New tests, adapted from
the existing ones.
* doc/misc/eshell.texi (Control Flow): Update documentation for
conditionals (bug#57129).
Diffstat (limited to 'doc/misc/eshell.texi')
| -rw-r--r-- | doc/misc/eshell.texi | 43 |
1 files changed, 24 insertions, 19 deletions
diff --git a/doc/misc/eshell.texi b/doc/misc/eshell.texi index d643cb50960..141c30ae9b9 100644 --- a/doc/misc/eshell.texi +++ b/doc/misc/eshell.texi @@ -1020,27 +1020,32 @@ Because Eshell commands can not (easily) be combined with lisp forms, Eshell provides command-oriented control flow statements for convenience. +Most of Eshell's control flow statements accept a @var{conditional}. +This can take a few different forms. If @var{conditional} is a dollar +expansion, the condition is satisfied if the result is a +non-@code{nil} value. If @var{conditional} is a @samp{@{ +@var{subcommand} @}}, the condition is satisfied if the +@var{subcommand}'s exit status is 0. + @table @code -@item if @{ @var{conditional} @} @{ @var{true-commands} @} -@itemx if @{ @var{conditional} @} @{ @var{true-commands} @} @{ @var{false-commands} @} -Evaluate @var{true-commands} if @var{conditional} returns success -(i.e.@: its exit code is zero); otherwise, evaluate -@var{false-commands}. - -@item unless @{ @var{conditional} @} @{ @var{false-commands} @} -@itemx unless @{ @var{conditional} @} @{ @var{false-commands} @} @{ @var{true-commands} @} -Evaluate @var{false-commands} if @var{conditional} returns failure -(i.e.@: its exit code is non-zero); otherwise, evaluate -@var{true-commands}. - -@item while @{ @var{conditional} @} @{ @var{commands} @} -Repeatedly evaluate @var{commands} so long as @var{conditional} -returns success. - -@item until @{ @var{conditional} @} @{ @var{commands} @} -Repeatedly evaluate @var{commands} so long as @var{conditional} -returns failure. +@item if @var{conditional} @{ @var{true-commands} @} +@itemx if @var{conditional} @{ @var{true-commands} @} @{ @var{false-commands} @} +Evaluate @var{true-commands} if @var{conditional} is satisfied; +otherwise, evaluate @var{false-commands}. + +@item unless @var{conditional} @{ @var{false-commands} @} +@itemx unless @var{conditional} @{ @var{false-commands} @} @{ @var{true-commands} @} +Evaluate @var{false-commands} if @var{conditional} is not satisfied; +otherwise, evaluate @var{true-commands}. + +@item while @var{conditional} @{ @var{commands} @} +Repeatedly evaluate @var{commands} so long as @var{conditional} is +satisfied. + +@item until @var{conditional} @{ @var{commands} @} +Repeatedly evaluate @var{commands} until @var{conditional} is +satisfied. @item for @var{var} in @var{list}@dots{} @{ @var{commands} @} Iterate over each element of of @var{list}, storing the element in |