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+The command returns the index of matching elements inside a Redis list. By
+default, when no options are given, it will scan the list from head to tail,
+looking for the first match of "element". If the element is found, its index
+(the zero-based position in the list) is returned. Otherwise, if no match is
+found, NULL is returned.
+
+```
+> RPUSH mylist a b c 1 2 3 c c
+> LPOS mylist c
+2
+```
+
+The optional arguments and options can modify the command's behavior. The `RANK`
+option specifies the "rank" of the first element to return, in case there are
+multiple matches. A rank of 1 means to return the first match, 2 to return the
+second match, and so forth.
+
+For instance, in the above example the element "c" is present multiple times, if
+I want the index of the second match, I'll write:
+
+```
+> LPOS mylist c RANK 2
+6
+```
+
+That is, the second occurrence of "c" is at position 6. A negative "rank" as the
+`RANK` argument tells `LPOS` to invert the search direction, starting from the
+tail to the head.
+
+So, we want to say, give me the first element starting from the tail of the
+list:
+
+```
+> LPOS mylist c RANK -1
+7
+```
+
+Note that the indexes are still reported in the "natural" way, that is,
+considering the first element starting from the head of the list at index 0, the
+next element at index 1, and so forth. This basically means that the returned
+indexes are stable whatever the rank is positive or negative.
+
+Sometimes we want to return not just the Nth matching element, but the position
+of all the first N matching elements. This can be achieved using the `COUNT`
+option.
+
+```
+> LPOS mylist c COUNT 2
+[2,6]
+```
+
+We can combine `COUNT` and `RANK`, so that `COUNT` will try to return up to the
+specified number of matches, but starting from the Nth match, as specified by
+the `RANK` option.
+
+```
+> LPOS mylist c RANK -1 COUNT 2
+[7,6]
+```
+
+When `COUNT` is used, it is possible to specify 0 as the number of matches, as a
+way to tell the command we want all the matches found returned as an array of
+indexes. This is better than giving a very large `COUNT` option because it is
+more general.
+
+```
+> LPOS mylist COUNT 0
+[2,6,7]
+```
+
+When `COUNT` is used and no match is found, an empty array is returned. However
+when `COUNT` is not used and there are no matches, the command returns NULL.
+
+Finally, the `MAXLEN` option tells the command to compare the provided element
+only with a given maximum number of list items. So for instance specifying
+`MAXLEN 1000` will make sure that the command performs only 1000 comparisons,
+effectively running the algorithm on a subset of the list (the first part or the
+last part depending on the fact we use a positive or negative rank). This is
+useful to limit the maximum complexity of the command. It is also useful when we
+expect the match to be found very early, but want to be sure that in case this
+is not true, the command does not take too much time to run.
+
+@return
+
+The command returns the integer representing the matching element, or null if
+there is no match. However, if the `COUNT` option is given the command returns
+an array (empty if there are no matches).
+
+@examples
+
+```cli
+RPUSH mylist a b c d 1 2 3 4 3 3 3
+LPOS mylist 3
+LPOS mylist 3 COUNT 0 RANK 2
+```