runtime(doc): clarify the effect of 'smarttab'
closes: #17426
Signed-off-by: Damien Lejay <damien@lejay.be>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 5c6fbfb..4471b7c 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -1,4 +1,4 @@
-*options.txt* For Vim version 9.1. Last change: 2025 Jun 02
+*options.txt* For Vim version 9.1. Last change: 2025 Jun 04
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -7803,19 +7803,14 @@
*'smarttab'* *'sta'* *'nosmarttab'* *'nosta'*
'smarttab' 'sta' boolean (default off)
global
- When on, a <Tab> in front of a line inserts blanks according to
- 'shiftwidth'. 'tabstop' or 'softtabstop' is used in other places. A
- <BS> will delete a 'shiftwidth' worth of space at the start of the
- line.
- When off, a <Tab> always inserts blanks according to 'tabstop' or
- 'softtabstop'. 'shiftwidth' is only used for shifting text left or
- right |shift-left-right|.
- What gets inserted (a <Tab> or spaces) depends on the 'expandtab'
- option. Also see |ins-expandtab|. When 'expandtab' is not set, the
- number of spaces is minimized by using <Tab>s.
- This option is reset when 'paste' is set and restored when 'paste' is
- reset.
- NOTE: This option is reset when 'compatible' is set.
+ When enabled, the <Tab> key will indent by 'shiftwidth' if the cursor
+ is in leading whitespace. The <BS> key has the opposite effect.
+ This behaves as if 'softtabstop' is set to the value of 'shiftwidth'.
+ This option is reset when 'compatible' is set; it is temporarily
+ disabled when 'paste' is enabled, and restored when 'paste' is turned
+ off.
+ Have a look at section |30.5| of the user guide for detailed
+ explanations on how Vim works with tabs and spaces.
*'smoothscroll'* *'sms'* *'nosmoothscroll'* *'nosms'*
'smoothscroll' 'sms' boolean (default off)