docs: auto-generate docs for `vim.lpeg` and `vim.re`

- Add section `VIM.LPEG` and `VIM.RE` to docs/lua.txt.

- Add `_meta/re.lua` which adds luadoc and type annotations, for the
  vendored `vim.re` package.

- Fix minor style issues on `_meta/lpeg.lua` luadoc for better vimdocs
  generation.

- Fix a bug on `gen_vimdoc` where non-helptags in verbatim code blocks
  were parsed as helptags, affecting code examples on `vim.lpeg.Cf`,
  etc.

- Also move the `vim.regex` section below so that it can be located
  closer to `vim.lpeg` and `vim.re`.

7 files changed, 588 insertions, 80 deletions

diff --git a/MAINTAIN.md b/MAINTAIN.md
index 6183270fd4..6e7f8d380f 100644
--- a/MAINTAIN.md
+++ b/MAINTAIN.md
@@ -156,8 +156,11 @@ These dependencies are "vendored" (inlined), we must update the sources manually
     * Run `scripts/gen_lsp.lua` to update.
 * `runtime/lua/vim/_meta/lpeg.lua`: LPeg definitions.
     * Refer to [`LuaCATS/lpeg`](https://github.com/LuaCATS/lpeg) for updates.
+    * Update the git SHA revision from which the documentation was taken.
 * `runtime/lua/vim/re.lua`: LPeg regex module.
     * Vendored from LPeg. Needs to be updated when LPeg is updated.
+* `runtime/lua/vim/_meta/re.lua`: docs for LPeg regex module.
+    * Needs to be updated when LPeg is updated.
 * `src/bit.c`: only for PUC lua: port of `require'bit'` from luajit https://bitop.luajit.org/
 * `runtime/lua/coxpcall.lua`: coxpcall (only needed for PUC lua, builtin to luajit)
 * `src/termkey`: [libtermkey](https://github.com/neovim/libtermkey)
diff --git a/runtime/doc/lua.txt b/runtime/doc/lua.txt
index aadc73e95c..924eb99e4e 100644
--- a/runtime/doc/lua.txt
+++ b/runtime/doc/lua.txt
@@ -572,13 +572,6 @@ A subset of the `vim.*` API is available in threads. This includes:
   like `vim.split`, `vim.tbl_*`, `vim.list_*`, and so on.
 - `vim.is_thread()` returns true from a non-main thread.
 
-------------------------------------------------------------------------------
-VIM.LPEG                                                            *lua-lpeg*
-
-                                                             *vim.lpeg* *vim.re*
-The Lpeg library for parsing expression grammars is being included as
-`vim.lpeg` (https://www.inf.puc-rio.br/~roberto/lpeg/). In addition, its regex-like
-interface is available as `vim.re` (https://www.inf.puc-rio.br/~roberto/lpeg/re.html).
 
 ==============================================================================
 VIM.HIGHLIGHT                                                  *vim.highlight*
@@ -647,49 +640,6 @@ vim.highlight.range({bufnr}, {ns}, {higroup}, {start}, {finish}, {opts})
 
 
 ==============================================================================
-VIM.REGEX                                                          *vim.regex*
-
-
-Vim regexes can be used directly from Lua. Currently they only allow
-matching within a single line.
-
-
-vim.regex({re})                                                  *vim.regex()*
-    Parse the Vim regex {re} and return a regex object. Regexes are "magic"
-    and case-sensitive by default, regardless of 'magic' and 'ignorecase'.
-    They can be controlled with flags, see |/magic| and |/ignorecase|.
-
-    Parameters: ~
-      • {re}  (`string`)
-
-    Return: ~
-        (`vim.regex`)
-
-                                                          *regex:match_line()*
-vim.regex:match_line({bufnr}, {line_idx}, {start}, {end_})
-    Match line {line_idx} (zero-based) in buffer {bufnr}. If {start} and {end}
-    are supplied, match only this byte index range. Otherwise see
-    |regex:match_str()|. If {start} is used, then the returned byte indices
-    will be relative {start}.
-
-    Parameters: ~
-      • {bufnr}     (`integer`)
-      • {line_idx}  (`integer`)
-      • {start}     (`integer?`)
-      • {end_}      (`integer?`)
-
-vim.regex:match_str({str})                                 *regex:match_str()*
-    Match the string against the regex. If the string should match the regex
-    precisely, surround the regex with `^` and `$` . If there was a match, the
-    byte indices for the beginning and end of the match are returned. When
-    there is no match, `nil` is returned. Because any integer is "truthy", `regex:match_str()` can
-    be directly used as a condition in an if-statement.
-
-    Parameters: ~
-      • {str}  (`string`)
-
-
-==============================================================================
 VIM.DIFF                                                            *vim.diff*
 
 vim.diff({a}, {b}, {opts})                                        *vim.diff()*
@@ -3035,6 +2985,478 @@ vim.glob.to_lpeg({pattern})                               *vim.glob.to_lpeg()*
 
 
 ==============================================================================
+VIM.LPEG                                                            *vim.lpeg*
+
+
+LPeg is a pattern-matching library for Lua, based on
+Parsing Expression Grammars (https://bford.info/packrat/) (PEGs).
+
+                                                                    *lua-lpeg*
+                                                            *vim.lpeg.Pattern*
+The LPeg library for parsing expression grammars is included as `vim.lpeg`
+(https://www.inf.puc-rio.br/~roberto/lpeg/).
+
+In addition, its regex-like interface is available as |vim.re|
+(https://www.inf.puc-rio.br/~roberto/lpeg/re.html).
+
+vim.lpeg.B({pattern})                                           *vim.lpeg.B()*
+    Returns a pattern that matches only if the input string at the current
+    position is preceded by `patt`. Pattern `patt` must match only strings
+    with some fixed length, and it cannot contain captures. Like the and
+    predicate, this pattern never consumes any input, independently of success
+    or failure.
+
+    Parameters: ~
+      • {pattern}  (`vim.lpeg.Pattern`)
+
+    Return: ~
+        (`vim.lpeg.Pattern`)
+
+vim.lpeg.C({patt})                                              *vim.lpeg.C()*
+    Creates a simple capture, which captures the substring of the subject that
+    matches `patt`. The captured value is a string. If `patt` has other
+    captures, their values are returned after this one.
+
+    Example: >lua
+        local function split (s, sep)
+          sep = lpeg.P(sep)
+          local elem = lpeg.C((1 - sep)^0)
+          local p = elem * (sep * elem)^0
+          return lpeg.match(p, s)
+        end
+        local a, b, c = split('a,b,c', ',')
+        assert(a == 'a')
+        assert(b == 'b')
+        assert(c == 'c')
+<
+
+    Parameters: ~
+      • {patt}  (`vim.lpeg.Pattern`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Carg({n})                                           *vim.lpeg.Carg()*
+    Creates an argument capture. This pattern matches the empty string and
+    produces the value given as the nth extra argument given in the call to `lpeg.match` .
+
+    Parameters: ~
+      • {n}  (`integer`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cb({name})                                            *vim.lpeg.Cb()*
+    Creates a back capture. This pattern matches the empty string and produces
+    the values produced by the most recent group capture named `name` (where
+    `name` can be any Lua value). Most recent means the last complete
+    outermost group capture with the given name. A Complete capture means that
+    the entire pattern corresponding to the capture has matched. An Outermost
+    capture means that the capture is not inside another complete capture. In
+    the same way that LPeg does not specify when it evaluates captures, it
+    does not specify whether it reuses values previously produced by the group
+    or re-evaluates them.
+
+    Parameters: ~
+      • {name}  (`any`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cc({...})                                             *vim.lpeg.Cc()*
+    Creates a constant capture. This pattern matches the empty string and
+    produces all given values as its captured values.
+
+    Parameters: ~
+      • {...}  (`any`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cf({patt}, {func})                                    *vim.lpeg.Cf()*
+    Creates a fold capture. If `patt` produces a list of captures C1 C2 ...
+    Cn, this capture will produce the value `func(...func(func(C1, C2),
+    C3)...,Cn)`, that is, it will fold (or accumulate, or reduce) the captures
+    from `patt` using function `func`. This capture assumes that `patt` should
+    produce at least one capture with at least one value (of any type), which
+    becomes the initial value of an accumulator. (If you need a specific
+    initial value, you may prefix a constant captureto `patt`.) For each
+    subsequent capture, LPeg calls `func` with this accumulator as the first
+    argument and all values produced by the capture as extra arguments; the
+    first result from this call becomes the new value for the accumulator. The
+    final value of the accumulator becomes the captured value.
+
+    Example: >lua
+        local number = lpeg.R("09") ^ 1 / tonumber
+        local list = number * ("," * number) ^ 0
+        local function add(acc, newvalue) return acc + newvalue end
+        local sum = lpeg.Cf(list, add)
+        assert(sum:match("10,30,43") == 83)
+<
+
+    Parameters: ~
+      • {patt}  (`vim.lpeg.Pattern`)
+      • {func}  (`fun(acc, newvalue)`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cg({patt}, {name})                                    *vim.lpeg.Cg()*
+    Creates a group capture. It groups all values returned by `patt` into a
+    single capture. The group may be anonymous (if no name is given) or named
+    with the given name (which can be any non-nil Lua value).
+
+    Parameters: ~
+      • {patt}  (`vim.lpeg.Pattern`)
+      • {name}  (`string?`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cmt({patt}, {fn})                                    *vim.lpeg.Cmt()*
+    Creates a match-time capture. Unlike all other captures, this one is
+    evaluated immediately when a match occurs (even if it is part of a larger
+    pattern that fails later). It forces the immediate evaluation of all its
+    nested captures and then calls `function`. The given function gets as
+    arguments the entire subject, the current position (after the match of
+    `patt`), plus any capture values produced by `patt`. The first value
+    returned by `function` defines how the match happens. If the call returns
+    a number, the match succeeds and the returned number becomes the new
+    current position. (Assuming a subject sand current position i, the
+    returned number must be in the range [i, len(s) + 1].) If the call returns
+    true, the match succeeds without consuming any input (so, to return true
+    is equivalent to return i). If the call returns false, nil, or no value,
+    the match fails. Any extra values returned by the function become the
+    values produced by the capture.
+
+    Parameters: ~
+      • {patt}  (`vim.lpeg.Pattern`)
+      • {fn}    (`function`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cp()                                                  *vim.lpeg.Cp()*
+    Creates a position capture. It matches the empty string and captures the
+    position in the subject where the match occurs. The captured value is a
+    number.
+
+    Example: >lua
+        local I = lpeg.Cp()
+        local function anywhere(p) return lpeg.P({I * p * I + 1 * lpeg.V(1)}) end
+        local match_start, match_end = anywhere("world"):match("hello world!")
+        assert(match_start == 7)
+        assert(match_end == 12)
+<
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Cs({patt})                                            *vim.lpeg.Cs()*
+    Creates a substitution capture. This function creates a substitution
+    capture, which captures the substring of the subject that matches `patt`,
+    with substitutions. For any capture inside `patt` with a value, the
+    substring that matched the capture is replaced by the capture value (which
+    should be a string). The final captured value is the string resulting from
+    all replacements.
+
+    Example: >lua
+        local function gsub (s, patt, repl)
+          patt = lpeg.P(patt)
+          patt = lpeg.Cs((patt / repl + 1)^0)
+          return lpeg.match(patt, s)
+        end
+        assert(gsub('Hello, xxx!', 'xxx', 'World') == 'Hello, World!')
+<
+
+    Parameters: ~
+      • {patt}  (`vim.lpeg.Pattern`)
+
+    Return: ~
+        (`vim.lpeg.Capture`)
+
+vim.lpeg.Ct({patt})                                            *vim.lpeg.Ct()*
+    Creates a table capture. This capture returns a table with all values from
+    all anonymous captures made by `patt` inside this table in successive
+    integer keys, starting at 1. Moreover, for each named capture group
+    created by `patt`, the first value of the group is put into the table with
+    the group name as its key. The captured value is only the table.
+
+    Parameters: ~
+      • {patt}  (vim.lpeg.Pattern |' `) @return (` vim.lpeg.Capture`)
+
+vim.lpeg.lpeg                                                     *vim.lpeg()*
+    LPeg is a new pattern-matching library for Lua, based on Parsing Expression
+    Grammars (PEGs).
+
+vim.lpeg.match({pattern}, {subject}, {init})                *vim.lpeg.match()*
+    Matches the given `pattern` against the `subject` string. If the match
+    succeeds, returns the index in the subject of the first character after
+    the match, or the captured values (if the pattern captured any value). An
+    optional numeric argument `init` makes the match start at that position in
+    the subject string. As usual in Lua libraries, a negative value counts
+    from the end. Unlike typical pattern-matching functions, `match` works
+    only in anchored mode; that is, it tries to match the pattern with a
+    prefix of the given subject string (at position `init`), not with an
+    arbitrary substring of the subject. So, if we want to find a pattern
+    anywhere in a string, we must either write a loop in Lua or write a
+    pattern that matches anywhere.
+
+    Example: >lua
+        local pattern = lpeg.R("az") ^ 1 * -1
+        assert(pattern:match("hello") == 6)
+        assert(lpeg.match(pattern, "hello") == 6)
+        assert(pattern:match("1 hello") == nil)
+<
+
+    Parameters: ~
+      • {pattern}  (`vim.lpeg.Pattern`)
+      • {subject}  (`string`)
+      • {init}     (`integer?`)
+
+    Return: ~
+        (`integer|vim.lpeg.Capture?`)
+
+vim.lpeg.P({value})                                             *vim.lpeg.P()*
+    Converts the given value into a proper pattern. This following rules are
+    applied:
+    • If the argument is a pattern, it is returned unmodified.
+    • If the argument is a string, it is translated to a pattern that matches
+      the string literally.
+    • If the argument is a non-negative number `n`, the result is a pattern
+      that matches exactly `n` characters.
+    • If the argument is a negative number `-n`, the result is a pattern that
+      succeeds only if the input string has less than `n` characters left:
+      `lpeg.P(-n)` is equivalent to `-lpeg.P(n)` (see the unary minus
+      operation).
+    • If the argument is a boolean, the result is a pattern that always
+      succeeds or always fails (according to the boolean value), without
+      consuming any input.
+    • If the argument is a table, it is interpreted as a grammar (see
+      Grammars).
+    • If the argument is a function, returns a pattern equivalent to a
+      match-time captureover the empty string.
+
+    Parameters: ~
+      • {value}  (`vim.lpeg.Pattern|string|integer|boolean|table|function`)
+
+    Return: ~
+        (`vim.lpeg.Pattern`)
+
+vim.lpeg.Pattern:match({subject}, {init})                    *Pattern:match()*
+    Matches the given `pattern` against the `subject` string. If the match
+    succeeds, returns the index in the subject of the first character after
+    the match, or the captured values (if the pattern captured any value). An
+    optional numeric argument `init` makes the match start at that position in
+    the subject string. As usual in Lua libraries, a negative value counts
+    from the end. Unlike typical pattern-matching functions, `match` works
+    only in anchored mode; that is, it tries to match the pattern with a
+    prefix of the given subject string (at position `init`), not with an
+    arbitrary substring of the subject. So, if we want to find a pattern
+    anywhere in a string, we must either write a loop in Lua or write a
+    pattern that matches anywhere.
+
+    Example: >lua
+        local pattern = lpeg.R("az") ^ 1 * -1
+        assert(pattern:match("hello") == 6)
+        assert(lpeg.match(pattern, "hello") == 6)
+        assert(pattern:match("1 hello") == nil)
+<
+
+    Parameters: ~
+      • {subject}  (`string`)
+      • {init}     (`integer?`)
+
+    Return: ~
+        (`integer|vim.lpeg.Capture?`)
+
+vim.lpeg.R({...})                                               *vim.lpeg.R()*
+    Returns a pattern that matches any single character belonging to one of
+    the given ranges. Each `range` is a string `xy` of length 2, representing
+    all characters with code between the codes of `x` and `y` (both
+    inclusive). As an example, the pattern `lpeg.R("09")` matches any digit,
+    and `lpeg.R("az", "AZ")` matches any ASCII letter.
+
+    Example: >lua
+        local pattern = lpeg.R("az") ^ 1 * -1
+        assert(pattern:match("hello") == 6)
+<
+
+    Parameters: ~
+      • {...}  (`string`)
+
+    Return: ~
+        (`vim.lpeg.Pattern`)
+
+vim.lpeg.S({string})                                            *vim.lpeg.S()*
+    Returns a pattern that matches any single character that appears in the
+    given string (the `S` stands for Set). As an example, the pattern
+    `lpeg.S("+-*&zwj;/")` matches any arithmetic operator. Note that, if `s`
+    is a character (that is, a string of length 1), then `lpeg.P(s)` is
+    equivalent to `lpeg.S(s)` which is equivalent to `lpeg.R(s..s)`. Note also
+    that both `lpeg.S("")` and `lpeg.R()` are patterns that always fail.
+
+    Parameters: ~
+      • {string}  (`string`)
+
+    Return: ~
+        (`vim.lpeg.Pattern`)
+
+vim.lpeg.setmaxstack({max})                           *vim.lpeg.setmaxstack()*
+    Sets a limit for the size of the backtrack stack used by LPeg to track
+    calls and choices. The default limit is `400`. Most well-written patterns
+    need little backtrack levels and therefore you seldom need to change this
+    limit; before changing it you should try to rewrite your pattern to avoid
+    the need for extra space. Nevertheless, a few useful patterns may
+    overflow. Also, with recursive grammars, subjects with deep recursion may
+    also need larger limits.
+
+    Parameters: ~
+      • {max}  (`integer`)
+
+vim.lpeg.type({value})                                       *vim.lpeg.type()*
+    Returns the string `"pattern"` if the given value is a pattern, otherwise
+    `nil`.
+
+    Return: ~
+        (`"pattern"?`)
+
+vim.lpeg.V({v})                                                 *vim.lpeg.V()*
+    Creates a non-terminal (a variable) for a grammar. This operation creates
+    a non-terminal (a variable) for a grammar. The created non-terminal refers
+    to the rule indexed by `v` in the enclosing grammar.
+
+    Example: >lua
+        local b = lpeg.P({"(" * ((1 - lpeg.S "()") + lpeg.V(1)) ^ 0 * ")"})
+        assert(b:match('((string))') == 11)
+        assert(b:match('(') == nil)
+<
+
+    Parameters: ~
+      • {v}  (`string|integer`)
+
+    Return: ~
+        (`vim.lpeg.Pattern`)
+
+vim.lpeg.version()                                        *vim.lpeg.version()*
+    Returns a string with the running version of LPeg.
+
+    Return: ~
+        (`string`)
+
+
+==============================================================================
+VIM.RE                                                                *vim.re*
+
+
+The `vim.re` module provides a conventional regex-like syntax for pattern usage
+within LPeg |vim.lpeg|.
+
+See https://www.inf.puc-rio.br/~roberto/lpeg/re.html for the original
+documentation including regex syntax and more concrete examples.
+
+vim.re.compile({string}, {defs})                            *vim.re.compile()*
+    Compiles the given {string} and returns an equivalent LPeg pattern. The
+    given string may define either an expression or a grammar. The optional
+    {defs} table provides extra Lua values to be used by the pattern.
+
+    Parameters: ~
+      • {string}  (`string`)
+      • {defs}    (`table?`)
+
+    Return: ~
+        (`vim.lpeg.Pattern`)
+
+vim.re.find({subject}, {pattern}, {init})                      *vim.re.find()*
+    Searches the given {pattern} in the given {subject}. If it finds a match,
+    returns the index where this occurrence starts and the index where it
+    ends. Otherwise, returns nil.
+
+    An optional numeric argument {init} makes the search starts at that
+    position in the subject string. As usual in Lua libraries, a negative
+    value counts from the end.
+
+    Parameters: ~
+      • {subject}  (`string`)
+      • {pattern}  (`vim.lpeg.Pattern|string`)
+      • {init}     (`integer?`)
+
+    Return (multiple): ~
+        (`integer?`) the index where the occurrence starts, nil if no match
+        (`integer?`) the index where the occurrence ends, nil if no match
+
+vim.re.gsub({subject}, {pattern}, {replacement})               *vim.re.gsub()*
+    Does a global substitution, replacing all occurrences of {pattern} in the
+    given {subject} by {replacement}.
+
+    Parameters: ~
+      • {subject}      (`string`)
+      • {pattern}      (`vim.lpeg.Pattern|string`)
+      • {replacement}  (`string`)
+
+    Return: ~
+        (`string`)
+
+vim.re.match({subject}, {pattern}, {init})                    *vim.re.match()*
+    Matches the given {pattern} against the given {subject}, returning all
+    captures.
+
+    Parameters: ~
+      • {subject}  (`string`)
+      • {pattern}  (`vim.lpeg.Pattern|string`)
+      • {init}     (`integer?`)
+
+    Return: ~
+        (`integer|vim.lpeg.Capture?`)
+
+    See also: ~
+      • vim.lpeg.match()
+
+
+==============================================================================
+VIM.REGEX                                                          *vim.regex*
+
+
+Vim regexes can be used directly from Lua. Currently they only allow
+matching within a single line.
+
+
+vim.regex({re})                                                  *vim.regex()*
+    Parse the Vim regex {re} and return a regex object. Regexes are "magic"
+    and case-sensitive by default, regardless of 'magic' and 'ignorecase'.
+    They can be controlled with flags, see |/magic| and |/ignorecase|.
+
+    Parameters: ~
+      • {re}  (`string`)
+
+    Return: ~
+        (`vim.regex`)
+
+                                                          *regex:match_line()*
+vim.regex:match_line({bufnr}, {line_idx}, {start}, {end_})
+    Match line {line_idx} (zero-based) in buffer {bufnr}. If {start} and {end}
+    are supplied, match only this byte index range. Otherwise see
+    |regex:match_str()|. If {start} is used, then the returned byte indices
+    will be relative {start}.
+
+    Parameters: ~
+      • {bufnr}     (`integer`)
+      • {line_idx}  (`integer`)
+      • {start}     (`integer?`)
+      • {end_}      (`integer?`)
+
+vim.regex:match_str({str})                                 *regex:match_str()*
+    Match the string against the regex. If the string should match the regex
+    precisely, surround the regex with `^` and `$` . If there was a match, the
+    byte indices for the beginning and end of the match are returned. When
+    there is no match, `nil` is returned. Because any integer is "truthy", `regex:match_str()` can
+    be directly used as a condition in an if-statement.
+
+    Parameters: ~
+      • {str}  (`string`)
+
+
+==============================================================================
 Lua module: vim.secure                                            *vim.secure*
 
 vim.secure.read({path})                                    *vim.secure.read()*
diff --git a/runtime/lua/vim/_meta/lpeg.lua b/runtime/lua/vim/_meta/lpeg.lua
index 42c9a6449e..5bd502a7c8 100644
--- a/runtime/lua/vim/_meta/lpeg.lua
+++ b/runtime/lua/vim/_meta/lpeg.lua
@@ -1,7 +1,24 @@
 --- @meta
+error('Cannot require a meta file')
 
--- These types were taken from https://github.com/LuaCATS/lpeg, with types being renamed to include
--- the vim namespace and with some descriptions made less verbose.
+-- These types were taken from https://github.com/LuaCATS/lpeg
+-- (based on revision 4aded588f9531d89555566bb1de27490354b91c7)
+-- with types being renamed to include the vim namespace and with some descriptions made less verbose.
+
+---@defgroup vim.lpeg
+---<pre>help
+---LPeg is a pattern-matching library for Lua, based on
+---Parsing Expression Grammars (https://bford.info/packrat/) (PEGs).
+---
+---                                                                    *lua-lpeg*
+---                                                            *vim.lpeg.Pattern*
+---The LPeg library for parsing expression grammars is included as `vim.lpeg`
+---(https://www.inf.puc-rio.br/~roberto/lpeg/).
+---
+---In addition, its regex-like interface is available as |vim.re|
+---(https://www.inf.puc-rio.br/~roberto/lpeg/re.html).
+---
+---</pre>
 
 --- *LPeg* is a new pattern-matching library for Lua, based on [Parsing Expression Grammars](https://bford.info/packrat/) (PEGs).
 vim.lpeg = {}
@@ -32,6 +49,7 @@ local Pattern = {}
 --- matches anywhere.
 ---
 --- Example:
+---
 --- ```lua
 --- local pattern = lpeg.R("az") ^ 1 * -1
 --- assert(pattern:match("hello") == 6)
@@ -55,6 +73,7 @@ function vim.lpeg.match(pattern, subject, init) end
 --- we must either write a loop in Lua or write a pattern that matches anywhere.
 ---
 --- Example:
+---
 --- ```lua
 --- local pattern = lpeg.R("az") ^ 1 * -1
 --- assert(pattern:match("hello") == 6)
@@ -69,7 +88,7 @@ function Pattern:match(subject, init) end
 
 --- Returns the string `"pattern"` if the given value is a pattern, otherwise `nil`.
 ---
---- @return 'pattern'|nil
+--- @return "pattern"|nil
 function vim.lpeg.type(value) end
 
 --- Returns a string with the running version of LPeg.
@@ -115,6 +134,7 @@ function vim.lpeg.B(pattern) end
 --- `lpeg.R("az", "AZ")` matches any ASCII letter.
 ---
 --- Example:
+---
 --- ```lua
 --- local pattern = lpeg.R("az") ^ 1 * -1
 --- assert(pattern:match("hello") == 6)
@@ -137,6 +157,7 @@ function vim.lpeg.S(string) end
 --- for a grammar. The created non-terminal refers to the rule indexed by `v` in the enclosing grammar.
 ---
 --- Example:
+---
 --- ```lua
 --- local b = lpeg.P({"(" * ((1 - lpeg.S "()") + lpeg.V(1)) ^ 0 * ")"})
 --- assert(b:match('((string))') == 11)
@@ -168,6 +189,7 @@ function vim.lpeg.V(v) end
 --- that table.
 ---
 --- Example:
+---
 --- ```lua
 --- lpeg.locale(lpeg)
 --- local space = lpeg.space^0
@@ -191,6 +213,7 @@ function vim.lpeg.locale(tab) end
 --- The captured value is a string. If `patt` has other captures, their values are returned after this one.
 ---
 --- Example:
+---
 --- ```lua
 --- local function split (s, sep)
 ---   sep = lpeg.P(sep)
@@ -241,6 +264,7 @@ function vim.lpeg.Cc(...) end
 --- becomes the captured value.
 ---
 --- Example:
+---
 --- ```lua
 --- local number = lpeg.R("09") ^ 1 / tonumber
 --- local list = number * ("," * number) ^ 0
@@ -267,6 +291,7 @@ function vim.lpeg.Cg(patt, name) end
 --- subject where the match occurs. The captured value is a number.
 ---
 --- Example:
+---
 --- ```lua
 --- local I = lpeg.Cp()
 --- local function anywhere(p) return lpeg.P({I * p * I + 1 * lpeg.V(1)}) end
@@ -285,6 +310,7 @@ function vim.lpeg.Cp() end
 --- value is the string resulting from all replacements.
 ---
 --- Example:
+---
 --- ```lua
 --- local function gsub (s, patt, repl)
 ---   patt = lpeg.P(patt)
diff --git a/runtime/lua/vim/_meta/re.lua b/runtime/lua/vim/_meta/re.lua
new file mode 100644
index 0000000000..4f254b19a0
--- /dev/null
+++ b/runtime/lua/vim/_meta/re.lua
@@ -0,0 +1,57 @@
+--- @meta
+error('Cannot require a meta file')
+
+-- Documentations and Lua types for vim.re (vendored re.lua, lpeg-1.1.0)
+-- https://www.inf.puc-rio.br/~roberto/lpeg/re.html
+--
+-- Copyright © 2007-2023 Lua.org, PUC-Rio.
+-- See 'lpeg.html' for license
+
+--- @defgroup vim.re
+---<pre>help
+---The `vim.re` module provides a conventional regex-like syntax for pattern usage
+---within LPeg |vim.lpeg|.
+---
+---See https://www.inf.puc-rio.br/~roberto/lpeg/re.html for the original
+---documentation including regex syntax and more concrete examples.
+---
+---</pre>
+
+--- Compiles the given {string} and returns an equivalent LPeg pattern. The given string may define
+--- either an expression or a grammar. The optional {defs} table provides extra Lua values to be used
+--- by the pattern.
+--- @param string string
+--- @param defs? table
+--- @return vim.lpeg.Pattern
+function vim.re.compile(string, defs) end
+
+--- Searches the given {pattern} in the given {subject}. If it finds a match, returns the index
+--- where this occurrence starts and the index where it ends. Otherwise, returns nil.
+---
+--- An optional numeric argument {init} makes the search starts at that position in the subject
+--- string. As usual in Lua libraries, a negative value counts from the end.
+--- @param subject string
+--- @param pattern vim.lpeg.Pattern|string
+--- @param init? integer
+--- @return integer|nil the index where the occurrence starts, nil if no match
+--- @return integer|nil the index where the occurrence ends, nil if no match
+function vim.re.find(subject, pattern, init) end
+
+--- Does a global substitution, replacing all occurrences of {pattern} in the given {subject} by
+--- {replacement}.
+--- @param subject string
+--- @param pattern vim.lpeg.Pattern|string
+--- @param replacement string
+--- @return string
+function vim.re.gsub(subject, pattern, replacement) end
+
+--- Matches the given {pattern} against the given {subject}, returning all captures.
+--- @param subject string
+--- @param pattern vim.lpeg.Pattern|string
+--- @param init? integer
+--- @return integer|vim.lpeg.Capture|nil
+--- @see vim.lpeg.match()
+function vim.re.match(subject, pattern, init) end
+
+--- Updates the pre-defined character classes to the current locale.
+function vim.re.updatelocale() end
diff --git a/runtime/lua/vim/re.lua b/runtime/lua/vim/re.lua
index 007eb27ed8..114f74eb80 100644
--- a/runtime/lua/vim/re.lua
+++ b/runtime/lua/vim/re.lua
@@ -3,6 +3,7 @@
 -- written by Roberto Ierusalimschy
 --
 --- vendored from lpeg-1.1.0
+--- documentation available at runtime/lua/vim/_meta/re.lua
 
 -- imported functions and modules
 local tonumber, type, print, error = tonumber, type, print, error
diff --git a/scripts/gen_vimdoc.py b/scripts/gen_vimdoc.py
index 01532cc3d3..4cb90a4588 100755
--- a/scripts/gen_vimdoc.py
+++ b/scripts/gen_vimdoc.py
@@ -202,7 +202,6 @@ CONFIG: Dict[str, Config] = {
         filename='lua.txt',
         section_order=[
             'highlight.lua',
-            'regex.lua',
             'diff.lua',
             'mpack.lua',
             'json.lua',
@@ -220,6 +219,9 @@ CONFIG: Dict[str, Config] = {
             'keymap.lua',
             'fs.lua',
             'glob.lua',
+            'lpeg.lua',
+            're.lua',
+            'regex.lua',
             'secure.lua',
             'version.lua',
             'iter.lua',
@@ -250,6 +252,8 @@ CONFIG: Dict[str, Config] = {
             'runtime/lua/vim/_meta/json.lua',
             'runtime/lua/vim/_meta/base64.lua',
             'runtime/lua/vim/_meta/regex.lua',
+            'runtime/lua/vim/_meta/lpeg.lua',
+            'runtime/lua/vim/_meta/re.lua',
             'runtime/lua/vim/_meta/spell.lua',
         ],
         file_patterns='*.lua',
@@ -268,7 +272,10 @@ CONFIG: Dict[str, Config] = {
         section_fmt=lambda name: (
             'Lua module: vim' if name.lower() == '_editor' else
             'LUA-VIMSCRIPT BRIDGE' if name.lower() == '_options' else
-            f'VIM.{name.upper()}' if name.lower() in [ 'highlight', 'mpack', 'json', 'base64', 'diff', 'spell', 'regex' ] else
+            f'VIM.{name.upper()}' if name.lower() in [
+                'highlight', 'mpack', 'json', 'base64', 'diff', 'spell',
+                'regex', 'lpeg', 're',
+            ] else
             'VIM' if name.lower() == 'builtin' else
             f'Lua module: vim.{name.lower()}'),
         helptag_fmt=lambda name: (
@@ -305,6 +312,8 @@ CONFIG: Dict[str, Config] = {
             'json': 'vim.json',
             'base64': 'vim.base64',
             'regex': 'vim.regex',
+            'lpeg': 'vim.lpeg',
+            're': 'vim.re',
             'spell': 'vim.spell',
             'snippet': 'vim.snippet',
             'text': 'vim.text',
@@ -1350,31 +1359,20 @@ def fmt_doxygen_xml_as_vimhelp(filename, target) -> Tuple[Docstring, Docstring]:
         # Verbatim handling.
         func_doc = re.sub(r'^\s+([<>])$', r'\1', func_doc, flags=re.M)
 
-        split_lines: List[str] = func_doc.split('\n')
-        start = 0
-        while True:
-            try:
-                start = split_lines.index('>', start)
-            except ValueError:
-                break
-
-            try:
-                end = split_lines.index('<', start)
-            except ValueError:
-                break
-
-            split_lines[start + 1:end] = [
-                ('    ' + x).rstrip()
-                for x in textwrap.dedent(
-                    "\n".join(
-                        split_lines[start+1:end]
-                    )
-                ).split("\n")
-            ]
-
-            start = end
-
-        func_doc = "\n".join(map(align_tags, split_lines))
+        def process_helptags(func_doc: str) -> str:
+            lines: List[str] = func_doc.split('\n')
+            # skip ">lang ... <" regions
+            is_verbatim: bool = False
+            for i in range(len(lines)):
+                if re.search(' >([a-z])*$', lines[i]):
+                    is_verbatim = True
+                elif is_verbatim and lines[i].strip() == '<':
+                    is_verbatim = False
+                if not is_verbatim:
+                    lines[i] = align_tags(lines[i])
+            return "\n".join(lines)
+
+        func_doc = process_helptags(func_doc)
 
         if (fn_name.startswith(config.fn_name_prefix)
             and fn_name != "nvim_error_event"):
diff --git a/src/nvim/CMakeLists.txt b/src/nvim/CMakeLists.txt
index 8e52542446..04072ffc3e 100644
--- a/src/nvim/CMakeLists.txt
+++ b/src/nvim/CMakeLists.txt
@@ -912,6 +912,7 @@ file(GLOB API_SOURCES CONFIGURE_DEPENDS ${PROJECT_SOURCE_DIR}/src/nvim/api/*.c)
 
 file(GLOB LUA_SOURCES CONFIGURE_DEPENDS
   ${NVIM_RUNTIME_DIR}/lua/vim/*.lua
+  ${NVIM_RUNTIME_DIR}/lua/vim/_meta/*.lua
   ${NVIM_RUNTIME_DIR}/lua/vim/filetype/*.lua
   ${NVIM_RUNTIME_DIR}/lua/vim/lsp/*.lua
   ${NVIM_RUNTIME_DIR}/lua/vim/treesitter/*.lua