diff --git a/doc_src/index.hdr.in b/doc_src/index.hdr.in
index 84ed5a551..34ed91cb7 100644
--- a/doc_src/index.hdr.in
+++ b/doc_src/index.hdr.in
@@ -80,7 +80,7 @@ while '-f' will turn it off.
\subsection quotes Quotes
-Sometimes features such as parameter expansion
+Sometimes features such as parameter expansion
and character escapes get in the way. When that
happens, the user can write a parameter within quotes, either '
(single quote) or " (double quote). There is one important difference
@@ -581,6 +581,9 @@ A command substitution will not change the value of the status variable outside of the command
substitution.
+Only part of the output can be used, see index
+range expansion for details.
+
Example:
The command echo (basename image.jpg .jpg).png will
@@ -674,6 +677,50 @@ element of the foo variable should be dereferenced and never that the fifth
element of the doubly dereferenced variable foo. The latter can
instead be expressed as $$foo[1][5].
+\subsection expand-index-range Index range expansion
+
+Both command substitution and environment variables support accessing only
+specific items by providing a set of indices in square brackets. It's
+often needed to access a sequence of elements. To do this, one can use
+range operator '..' for this. A range 'a..b', where range limits 'a' and 'b'
+are integer numbers, is expanded into a sequence of indices
+'a a+1 a+2 ... b' or 'a a-1 a-2 ... b' depending on which of 'a' or 'b'
+is higher. The negative range limits are calculated from the end of the array
+or command substitution.
+
+Some examples:
+
+# Limit the command substitution output
+echo (seq 10)[2..5] # will use elements from 2 to 5
+# Output is:
+# 2 3 4 5
+
+# Use overlapping ranges:
+echo (seq 10)[2..5 1..3] # will take elements from 2 to 5 and then elements from 1 to 3
+# Output is:
+# 2 3 4 5 1 2 3
+
+# Reverse output
+echo (seq 10)[-1..1] # will use elements from the last output line to the first one in reverse direction
+# Output is:
+# 10 9 8 7 6 5 4 3 2 1
+
+
+The same works when setting or expanding variables:
+
+# Reverse path variable
+set PATH $PATH[-1..1]
+# or
+set PATH[-1..1] $PATH
+
+# Use only n last items of the PATH
+set n -3
+echo $PATH[$n..-1]
+
+
+NOTE: Currently variables are allowed inside variables index expansion, but not in indices,
+used for command substitution.
+
\subsection expand-home Home directory expansion
The ~ (tilde) character at the beginning of a parameter, followed by a
@@ -909,6 +956,9 @@ If you specify a negative index when expanding or assigning to an
array variable, the index will be calculated from the end of the
array. For example, the index -1 means the last index of an array.
+A range of indices can be specified, see index
+range expansion for details.
+
\subsection variables-special Special variables
The user can change the settings of \c fish by changing the values of