update l-lpeg l-url

1 files changed, 769 insertions, 68 deletions

diff --git a/lualibs-lpeg.lua b/lualibs-lpeg.lua
index b107a8e..d92b722 100644
--- a/lualibs-lpeg.lua
+++ b/lualibs-lpeg.lua
@@ -6,30 +6,124 @@ if not modules then modules = { } end modules ['l-lpeg'] = {
     license   = "see context related readme files"
 }
 
+
+-- a new lpeg fails on a #(1-P(":")) test and really needs a + P(-1)
+
 local lpeg = require("lpeg")
 
+-- tracing (only used when we encounter a problem in integration of lpeg in luatex)
+
+-- some code will move to unicode and string
+
+local report = texio and texio.write_nl or print
+
+-- local lpmatch = lpeg.match
+-- local lpprint = lpeg.print
+-- local lpp     = lpeg.P
+-- local lpr     = lpeg.R
+-- local lps     = lpeg.S
+-- local lpc     = lpeg.C
+-- local lpb     = lpeg.B
+-- local lpv     = lpeg.V
+-- local lpcf    = lpeg.Cf
+-- local lpcb    = lpeg.Cb
+-- local lpcg    = lpeg.Cg
+-- local lpct    = lpeg.Ct
+-- local lpcs    = lpeg.Cs
+-- local lpcc    = lpeg.Cc
+-- local lpcmt   = lpeg.Cmt
+-- local lpcarg  = lpeg.Carg
+
+-- function lpeg.match(l,...) report("LPEG MATCH") lpprint(l) return lpmatch(l,...) end
+
+-- function lpeg.P    (l) local p = lpp   (l) report("LPEG P =")    lpprint(l) return p end
+-- function lpeg.R    (l) local p = lpr   (l) report("LPEG R =")    lpprint(l) return p end
+-- function lpeg.S    (l) local p = lps   (l) report("LPEG S =")    lpprint(l) return p end
+-- function lpeg.C    (l) local p = lpc   (l) report("LPEG C =")    lpprint(l) return p end
+-- function lpeg.B    (l) local p = lpb   (l) report("LPEG B =")    lpprint(l) return p end
+-- function lpeg.V    (l) local p = lpv   (l) report("LPEG V =")    lpprint(l) return p end
+-- function lpeg.Cf   (l) local p = lpcf  (l) report("LPEG Cf =")   lpprint(l) return p end
+-- function lpeg.Cb   (l) local p = lpcb  (l) report("LPEG Cb =")   lpprint(l) return p end
+-- function lpeg.Cg   (l) local p = lpcg  (l) report("LPEG Cg =")   lpprint(l) return p end
+-- function lpeg.Ct   (l) local p = lpct  (l) report("LPEG Ct =")   lpprint(l) return p end
+-- function lpeg.Cs   (l) local p = lpcs  (l) report("LPEG Cs =")   lpprint(l) return p end
+-- function lpeg.Cc   (l) local p = lpcc  (l) report("LPEG Cc =")   lpprint(l) return p end
+-- function lpeg.Cmt  (l) local p = lpcmt (l) report("LPEG Cmt =")  lpprint(l) return p end
+-- function lpeg.Carg (l) local p = lpcarg(l) report("LPEG Carg =") lpprint(l) return p end
+
+local type, next = type, next
+local byte, char, gmatch, format = string.byte, string.char, string.gmatch, string.format
+
+-- Beware, we predefine a bunch of patterns here and one reason for doing so
+-- is that we get consistent behaviour in some of the visualizers.
+
 lpeg.patterns  = lpeg.patterns or { } -- so that we can share
 local patterns = lpeg.patterns
 
-local P, R, S, Ct, C, Cs, Cc, V = lpeg.P, lpeg.R, lpeg.S, lpeg.Ct, lpeg.C, lpeg.Cs, lpeg.Cc, lpeg.V
-local match = lpeg.match
+local P, R, S, V, Ct, C, Cs, Cc, Cp = lpeg.P, lpeg.R, lpeg.S, lpeg.V, lpeg.Ct, lpeg.C, lpeg.Cs, lpeg.Cc, lpeg.Cp
+local lpegtype, lpegmatch = lpeg.type, lpeg.match
+
+local utfcharacters    = string.utfcharacters
+local utfgmatch        = unicode and unicode.utf8.gmatch
+
+local anything         = P(1)
+local endofstring      = P(-1)
+local alwaysmatched    = P(true)
+
+patterns.anything      = anything
+patterns.endofstring   = endofstring
+patterns.beginofstring = alwaysmatched
+patterns.alwaysmatched = alwaysmatched
 
 local digit, sign      = R('09'), S('+-')
 local cr, lf, crlf     = P("\r"), P("\n"), P("\r\n")
-local utf8byte         = R("\128\191")
+local newline          = crlf + S("\r\n") -- cr + lf
+local escaped          = P("\\") * anything
+local squote           = P("'")
+local dquote           = P('"')
+local space            = P(" ")
+
+local utfbom_32_be     = P('\000\000\254\255')
+local utfbom_32_le     = P('\255\254\000\000')
+local utfbom_16_be     = P('\255\254')
+local utfbom_16_le     = P('\254\255')
+local utfbom_8         = P('\239\187\191')
+local utfbom           = utfbom_32_be + utfbom_32_le
+                       + utfbom_16_be + utfbom_16_le
+                       + utfbom_8
+local utftype          = utfbom_32_be / "utf-32-be" + utfbom_32_le  / "utf-32-le"
+                       + utfbom_16_be / "utf-16-be" + utfbom_16_le  / "utf-16-le"
+                       + utfbom_8     / "utf-8"     + alwaysmatched / "unknown"
+
+local utf8next         = R("\128\191")
 
-patterns.utf8byte      = utf8byte
 patterns.utf8one       = R("\000\127")
-patterns.utf8two       = R("\194\223") * utf8byte
-patterns.utf8three     = R("\224\239") * utf8byte * utf8byte
-patterns.utf8four      = R("\240\244") * utf8byte * utf8byte * utf8byte
+patterns.utf8two       = R("\194\223") * utf8next
+patterns.utf8three     = R("\224\239") * utf8next * utf8next
+patterns.utf8four      = R("\240\244") * utf8next * utf8next * utf8next
+patterns.utfbom        = utfbom
+patterns.utftype       = utftype
+
+local utf8char         = patterns.utf8one + patterns.utf8two + patterns.utf8three + patterns.utf8four
+local validutf8char    = utf8char^0 * endofstring * Cc(true) + Cc(false)
+
+patterns.utf8          = utf8char
+patterns.utf8char      = utf8char
+patterns.validutf8     = validutf8char
+patterns.validutf8char = validutf8char
+
+local eol              = S("\n\r")
+local spacer           = S(" \t\f\v")  -- + char(0xc2, 0xa0) if we want utf (cf mail roberto)
+local whitespace       = eol + spacer
 
 patterns.digit         = digit
 patterns.sign          = sign
 patterns.cardinal      = sign^0 * digit^1
 patterns.integer       = sign^0 * digit^1
 patterns.float         = sign^0 * digit^0 * P('.') * digit^1
+patterns.cfloat        = sign^0 * digit^0 * P(',') * digit^1
 patterns.number        = patterns.float + patterns.integer
+patterns.cnumber       = patterns.cfloat + patterns.integer
 patterns.oct           = P("0") * R("07")^1
 patterns.octal         = patterns.oct
 patterns.HEX           = P("0x") * R("09","AF")^1
@@ -38,55 +132,83 @@ patterns.hexadecimal   = P("0x") * R("09","AF","af")^1
 patterns.lowercase     = R("az")
 patterns.uppercase     = R("AZ")
 patterns.letter        = patterns.lowercase + patterns.uppercase
-patterns.space         = S(" ")
-patterns.eol           = S("\n\r")
-patterns.spacer        = S(" \t\f\v")  -- + string.char(0xc2, 0xa0) if we want utf (cf mail roberto)
-patterns.newline       = crlf + cr + lf
-patterns.nonspace      = 1 - patterns.space
-patterns.nonspacer     = 1 - patterns.spacer
-patterns.whitespace    = patterns.eol + patterns.spacer
-patterns.nonwhitespace = 1 - patterns.whitespace
-patterns.utf8          = patterns.utf8one + patterns.utf8two + patterns.utf8three + patterns.utf8four
-patterns.utfbom        = P('\000\000\254\255') + P('\255\254\000\000') + P('\255\254') + P('\254\255') + P('\239\187\191')
+patterns.space         = space
+patterns.tab           = P("\t")
+patterns.spaceortab    = patterns.space + patterns.tab
+patterns.eol           = eol
+patterns.spacer        = spacer
+patterns.whitespace    = whitespace
+patterns.newline       = newline
+patterns.emptyline     = newline^1
+patterns.nonspacer     = 1 - spacer
+patterns.nonwhitespace = 1 - whitespace
+patterns.equal         = P("=")
+patterns.comma         = P(",")
+patterns.commaspacer   = P(",") * spacer^0
+patterns.period        = P(".")
+patterns.colon         = P(":")
+patterns.semicolon     = P(";")
+patterns.underscore    = P("_")
+patterns.escaped       = escaped
+patterns.squote        = squote
+patterns.dquote        = dquote
+patterns.nosquote      = (escaped + (1-squote))^0
+patterns.nodquote      = (escaped + (1-dquote))^0
+patterns.unsingle      = (squote/"") * patterns.nosquote * (squote/"")
+patterns.undouble      = (dquote/"") * patterns.nodquote * (dquote/"")
+patterns.unquoted      = patterns.undouble + patterns.unsingle -- more often undouble
+patterns.unspacer      = ((patterns.spacer^1)/"")^0
 
-function lpeg.anywhere(pattern) --slightly adapted from website
-    return P { P(pattern) + 1 * V(1) } -- why so complex?
-end
+patterns.singlequoted  = squote * patterns.nosquote * squote
+patterns.doublequoted  = dquote * patterns.nodquote * dquote
+patterns.quoted        = patterns.doublequoted + patterns.singlequoted
 
-function lpeg.splitter(pattern, action)
-    return (((1-P(pattern))^1)/action+1)^0
+patterns.somecontent   = (anything - newline - space)^1 -- (utf8char - newline - space)^1
+patterns.beginline     = #(1-newline)
+
+-- print(string.unquoted("test"))
+-- print(string.unquoted([["t\"est"]]))
+-- print(string.unquoted([["t\"est"x]]))
+-- print(string.unquoted("\'test\'"))
+-- print(string.unquoted('"test"'))
+-- print(string.unquoted('"test"'))
+
+local function anywhere(pattern) --slightly adapted from website
+    return P { P(pattern) + 1 * V(1) }
 end
 
-local spacing  = patterns.spacer^0 * patterns.newline -- sort of strip
-local empty    = spacing * Cc("")
-local nonempty = Cs((1-spacing)^1) * spacing^-1
-local content  = (empty + nonempty)^1
+lpeg.anywhere = anywhere
 
-local capture = Ct(content^0)
+function lpeg.instringchecker(p)
+    p = anywhere(p)
+    return function(str)
+        return lpegmatch(p,str) and true or false
+    end
+end
 
-function string:splitlines()
-    return match(capture,self)
+function lpeg.splitter(pattern, action)
+    return (((1-P(pattern))^1)/action+1)^0
 end
 
-patterns.textline = content
+function lpeg.tsplitter(pattern, action)
+    return Ct((((1-P(pattern))^1)/action+1)^0)
+end
 
---~ local p = lpeg.splitat("->",false)  print(match(p,"oeps->what->more"))  -- oeps what more
---~ local p = lpeg.splitat("->",true)   print(match(p,"oeps->what->more"))  -- oeps what->more
---~ local p = lpeg.splitat("->",false)  print(match(p,"oeps"))              -- oeps
---~ local p = lpeg.splitat("->",true)   print(match(p,"oeps"))              -- oeps
+-- probleem: separator can be lpeg and that does not hash too well, but
+-- it's quite okay as the key is then not garbage collected
 
-local splitters_s, splitters_m = { }, { }
+local splitters_s, splitters_m, splitters_t = { }, { }, { }
 
 local function splitat(separator,single)
     local splitter = (single and splitters_s[separator]) or splitters_m[separator]
     if not splitter then
         separator = P(separator)
+        local other = C((1 - separator)^0)
         if single then
-            local other, any = C((1 - separator)^0), P(1)
+            local any = anything
             splitter = other * (separator * C(any^0) + "") -- ?
             splitters_s[separator] = splitter
         else
-            local other = C((1 - separator)^0)
             splitter = other * (separator * other)^0
             splitters_m[separator] = splitter
         end
@@ -94,29 +216,135 @@ local function splitat(separator,single)
     return splitter
 end
 
-lpeg.splitat = splitat
+local function tsplitat(separator)
+    local splitter = splitters_t[separator]
+    if not splitter then
+        splitter = Ct(splitat(separator))
+        splitters_t[separator] = splitter
+    end
+    return splitter
+end
+
+lpeg.splitat  = splitat
+lpeg.tsplitat = tsplitat
+
+function string.splitup(str,separator)
+    if not separator then
+        separator = ","
+    end
+    return lpegmatch(splitters_m[separator] or splitat(separator),str)
+end
+
+--~ local p = splitat("->",false)  print(lpegmatch(p,"oeps->what->more"))  -- oeps what more
+--~ local p = splitat("->",true)   print(lpegmatch(p,"oeps->what->more"))  -- oeps what->more
+--~ local p = splitat("->",false)  print(lpegmatch(p,"oeps"))              -- oeps
+--~ local p = splitat("->",true)   print(lpegmatch(p,"oeps"))              -- oeps
 
 local cache = { }
 
 function lpeg.split(separator,str)
     local c = cache[separator]
     if not c then
-        c = Ct(splitat(separator))
+        c = tsplitat(separator)
         cache[separator] = c
     end
-    return match(c,str)
+    return lpegmatch(c,str)
 end
 
-function string:split(separator)
-    local c = cache[separator]
-    if not c then
-        c = Ct(splitat(separator))
-        cache[separator] = c
+function string.split(str,separator)
+    if separator then
+        local c = cache[separator]
+        if not c then
+            c = tsplitat(separator)
+            cache[separator] = c
+        end
+        return lpegmatch(c,str)
+    else
+        return { str }
     end
-    return match(c,self)
 end
 
-lpeg.splitters = cache
+local spacing  = patterns.spacer^0 * newline -- sort of strip
+local empty    = spacing * Cc("")
+local nonempty = Cs((1-spacing)^1) * spacing^-1
+local content  = (empty + nonempty)^1
+
+patterns.textline = content
+
+--~ local linesplitter = Ct(content^0)
+--~
+--~ function string.splitlines(str)
+--~     return lpegmatch(linesplitter,str)
+--~ end
+
+local linesplitter = tsplitat(newline)
+
+patterns.linesplitter = linesplitter
+
+function string.splitlines(str)
+    return lpegmatch(linesplitter,str)
+end
+
+local utflinesplitter = utfbom^-1 * tsplitat(newline)
+
+patterns.utflinesplitter = utflinesplitter
+
+function string.utfsplitlines(str)
+    return lpegmatch(utflinesplitter,str or "")
+end
+
+local utfcharsplitter_ows = utfbom^-1 * Ct(C(utf8char)^0)
+local utfcharsplitter_iws = utfbom^-1 * Ct((whitespace^1 + C(utf8char))^0)
+
+function string.utfsplit(str,ignorewhitespace) -- new
+    if ignorewhitespace then
+        return lpegmatch(utfcharsplitter_iws,str or "")
+    else
+        return lpegmatch(utfcharsplitter_ows,str or "")
+    end
+end
+
+-- inspect(string.utfsplit("a b c d"))
+-- inspect(string.utfsplit("a b c d",true))
+
+-- -- alternative 1: 0.77
+--
+-- local utfcharcounter = utfbom^-1 * Cs((utf8char/'!')^0)
+--
+-- function string.utflength(str)
+--     return #lpegmatch(utfcharcounter,str or "")
+-- end
+--
+-- -- alternative 2: 1.70
+--
+-- local n = 0
+--
+-- local utfcharcounter = utfbom^-1 * (utf8char/function() n = n + 1 end)^0 -- slow
+--
+-- function string.utflength(str)
+--     n = 0
+--     lpegmatch(utfcharcounter,str or "")
+--     return n
+-- end
+--
+-- -- alternative 3: 0.24 (native unicode.utf8.len: 0.047)
+
+local n = 0
+
+local utfcharcounter = utfbom^-1 * Cs ( (
+    Cp() * (lpeg.patterns.utf8one  )^1 * Cp() / function(f,t) n = n +  t - f    end
+  + Cp() * (lpeg.patterns.utf8two  )^1 * Cp() / function(f,t) n = n + (t - f)/2 end
+  + Cp() * (lpeg.patterns.utf8three)^1 * Cp() / function(f,t) n = n + (t - f)/3 end
+  + Cp() * (lpeg.patterns.utf8four )^1 * Cp() / function(f,t) n = n + (t - f)/4 end
+)^0 )
+
+function string.utflength(str)
+    n = 0
+    lpegmatch(utfcharcounter,str or "")
+    return n
+end
+
+--~ lpeg.splitters = cache -- no longer public
 
 local cache = { }
 
@@ -124,42 +352,515 @@ function lpeg.checkedsplit(separator,str)
     local c = cache[separator]
     if not c then
         separator = P(separator)
-        local other = C((1 - separator)^0)
+        local other = C((1 - separator)^1)
         c = Ct(separator^0 * other * (separator^1 * other)^0)
         cache[separator] = c
     end
-    return match(c,str)
+    return lpegmatch(c,str)
 end
 
-function string:checkedsplit(separator)
+function string.checkedsplit(str,separator)
     local c = cache[separator]
     if not c then
         separator = P(separator)
-        local other = C((1 - separator)^0)
+        local other = C((1 - separator)^1)
         c = Ct(separator^0 * other * (separator^1 * other)^0)
         cache[separator] = c
     end
-    return match(c,self)
+    return lpegmatch(c,str)
+end
+
+--~ from roberto's site:
+
+local function f2(s) local c1, c2         = byte(s,1,2) return   c1 * 64 + c2                       -    12416 end
+local function f3(s) local c1, c2, c3     = byte(s,1,3) return  (c1 * 64 + c2) * 64 + c3            -   925824 end
+local function f4(s) local c1, c2, c3, c4 = byte(s,1,4) return ((c1 * 64 + c2) * 64 + c3) * 64 + c4 - 63447168 end
+
+local utf8byte = patterns.utf8one/byte + patterns.utf8two/f2 + patterns.utf8three/f3 + patterns.utf8four/f4
+
+patterns.utf8byte = utf8byte
+
+--~ local str = " a b c d "
+
+--~ local s = lpeg.stripper(lpeg.R("az"))   print("["..lpegmatch(s,str).."]")
+--~ local s = lpeg.keeper(lpeg.R("az"))     print("["..lpegmatch(s,str).."]")
+--~ local s = lpeg.stripper("ab")           print("["..lpegmatch(s,str).."]")
+--~ local s = lpeg.keeper("ab")             print("["..lpegmatch(s,str).."]")
+
+local cache = { }
+
+function lpeg.stripper(str)
+    if type(str) == "string" then
+        local s = cache[str]
+        if not s then
+            s = Cs(((S(str)^1)/"" + 1)^0)
+            cache[str] = s
+        end
+        return s
+    else
+        return Cs(((str^1)/"" + 1)^0)
+    end
+end
+
+local cache = { }
+
+function lpeg.keeper(str)
+    if type(str) == "string" then
+        local s = cache[str]
+        if not s then
+            s = Cs((((1-S(str))^1)/"" + 1)^0)
+            cache[str] = s
+        end
+        return s
+    else
+        return Cs((((1-str)^1)/"" + 1)^0)
+    end
+end
+
+function lpeg.frontstripper(str) -- or pattern (yet undocumented)
+    return (P(str) + P(true)) * Cs(anything^0)
+end
+
+function lpeg.endstripper(str) -- or pattern (yet undocumented)
+    return Cs((1 - P(str) * endofstring)^0)
+end
+
+-- Just for fun I looked at the used bytecode and
+-- p = (p and p + pp) or pp gets one more (testset).
+
+function lpeg.replacer(one,two)
+    if type(one) == "table" then
+        local no = #one
+        local p
+        if no == 0 then
+            for k, v in next, one do
+                local pp = P(k) / v
+                if p then
+                    p = p + pp
+                else
+                    p = pp
+                end
+            end
+            return Cs((p + 1)^0)
+        elseif no == 1 then
+            local o = one[1]
+            one, two = P(o[1]), o[2]
+            return Cs(((1-one)^1 + one/two)^0)
+        else
+            for i=1,no do
+                local o = one[i]
+                local pp = P(o[1]) / o[2]
+                if p then
+                    p = p + pp
+                else
+                    p = pp
+                end
+            end
+            return Cs((p + 1)^0)
+        end
+    else
+        one = P(one)
+        two = two or ""
+        return Cs(((1-one)^1 + one/two)^0)
+    end
 end
 
---~ function lpeg.append(list,pp)
---~     local p = pp
---~     for l=1,#list do
---~         if p then
---~             p = p + P(list[l])
---~         else
---~             p = P(list[l])
---~         end
---~     end
---~     return p
+-- print(lpeg.match(lpeg.replacer("e","a"),"test test"))
+-- print(lpeg.match(lpeg.replacer{{"e","a"}},"test test"))
+-- print(lpeg.match(lpeg.replacer({ e = "a", t = "x" }),"test test"))
+
+local splitters_f, splitters_s = { }, { }
+
+function lpeg.firstofsplit(separator) -- always return value
+    local splitter = splitters_f[separator]
+    if not splitter then
+        separator = P(separator)
+        splitter = C((1 - separator)^0)
+        splitters_f[separator] = splitter
+    end
+    return splitter
+end
+
+function lpeg.secondofsplit(separator) -- nil if not split
+    local splitter = splitters_s[separator]
+    if not splitter then
+        separator = P(separator)
+        splitter = (1 - separator)^0 * separator * C(anything^0)
+        splitters_s[separator] = splitter
+    end
+    return splitter
+end
+
+function lpeg.balancer(left,right)
+    left, right = P(left), P(right)
+    return P { left * ((1 - left - right) + V(1))^0 * right }
+end
+
+--~ print(1,lpegmatch(lpeg.firstofsplit(":"),"bc:de"))
+--~ print(2,lpegmatch(lpeg.firstofsplit(":"),":de")) -- empty
+--~ print(3,lpegmatch(lpeg.firstofsplit(":"),"bc"))
+--~ print(4,lpegmatch(lpeg.secondofsplit(":"),"bc:de"))
+--~ print(5,lpegmatch(lpeg.secondofsplit(":"),"bc:")) -- empty
+--~ print(6,lpegmatch(lpeg.secondofsplit(":",""),"bc"))
+--~ print(7,lpegmatch(lpeg.secondofsplit(":"),"bc"))
+--~ print(9,lpegmatch(lpeg.secondofsplit(":","123"),"bc"))
+
+--~ -- slower:
+--~
+--~ function lpeg.counter(pattern)
+--~     local n, pattern = 0, (lpeg.P(pattern)/function() n = n + 1 end  + lpeg.anything)^0
+--~     return function(str) n = 0 ; lpegmatch(pattern,str) ; return n end
 --~ end
 
---~ from roberto's site:
+local nany = utf8char/""
+
+function lpeg.counter(pattern)
+    pattern = Cs((P(pattern)/" " + nany)^0)
+    return function(str)
+        return #lpegmatch(pattern,str)
+    end
+end
+
+if utfgmatch then
+
+    function lpeg.count(str,what) -- replaces string.count
+        if type(what) == "string" then
+            local n = 0
+            for _ in utfgmatch(str,what) do
+                n = n + 1
+            end
+            return n
+        else -- 4 times slower but still faster than / function
+            return #lpegmatch(Cs((P(what)/" " + nany)^0),str)
+        end
+    end
+
+else
+
+    local cache = { }
+
+    function lpeg.count(str,what) -- replaces string.count
+        if type(what) == "string" then
+            local p = cache[what]
+            if not p then
+                p = Cs((P(what)/" " + nany)^0)
+                cache[p] = p
+            end
+            return #lpegmatch(p,str)
+        else -- 4 times slower but still faster than / function
+            return #lpegmatch(Cs((P(what)/" " + nany)^0),str)
+        end
+    end
+
+end
+
+local patterns_escapes = { -- also defines in l-string
+    ["%"] = "%%",
+    ["."] = "%.",
+    ["+"] = "%+", ["-"] = "%-", ["*"] = "%*",
+    ["["] = "%[", ["]"] = "%]",
+    ["("] = "%)", [")"] = "%)",
+ -- ["{"] = "%{", ["}"] = "%}"
+ -- ["^"] = "%^", ["$"] = "%$",
+}
+
+local simple_escapes = { -- also defines in l-string
+    ["-"] = "%-",
+    ["."] = "%.",
+    ["?"] = ".",
+    ["*"] = ".*",
+}
+
+local p = Cs((S("-.+*%()[]") / patterns_escapes + anything)^0)
+local s = Cs((S("-.+*%()[]") / simple_escapes   + anything)^0)
+
+function string.escapedpattern(str,simple)
+    return lpegmatch(simple and s or p,str)
+end
+
+-- utf extensies
+
+lpeg.UP = lpeg.P
+
+if utfcharacters then
+
+    function lpeg.US(str)
+        local p
+        for uc in utfcharacters(str) do
+            if p then
+                p = p + P(uc)
+            else
+                p = P(uc)
+            end
+        end
+        return p
+    end
+
+
+elseif utfgmatch then
+
+    function lpeg.US(str)
+        local p
+        for uc in utfgmatch(str,".") do
+            if p then
+                p = p + P(uc)
+            else
+                p = P(uc)
+            end
+        end
+        return p
+    end
+
+else
 
-local f1 = string.byte
+    function lpeg.US(str)
+        local p
+        local f = function(uc)
+            if p then
+                p = p + P(uc)
+            else
+                p = P(uc)
+            end
+        end
+        lpegmatch((utf8char/f)^0,str)
+        return p
+    end
+
+end
+
+local range = Cs(utf8byte) * (Cs(utf8byte) + Cc(false))
+
+local utfchar = unicode and unicode.utf8 and unicode.utf8.char
+
+function lpeg.UR(str,more)
+    local first, last
+    if type(str) == "number" then
+        first = str
+        last = more or first
+    else
+        first, last = lpegmatch(range,str)
+        if not last then
+            return P(str)
+        end
+    end
+    if first == last then
+        return P(str)
+    elseif utfchar and last - first < 8 then -- a somewhat arbitrary criterium
+        local p
+        for i=first,last do
+            if p then
+                p = p + P(utfchar(i))
+            else
+                p = P(utfchar(i))
+            end
+        end
+        return p -- nil when invalid range
+    else
+        local f = function(b)
+            return b >= first and b <= last
+        end
+        return utf8byte / f -- nil when invalid range
+    end
+end
 
-local function f2(s) local c1, c2         = f1(s,1,2) return   c1 * 64 + c2                       -    12416 end
-local function f3(s) local c1, c2, c3     = f1(s,1,3) return  (c1 * 64 + c2) * 64 + c3            -   925824 end
-local function f4(s) local c1, c2, c3, c4 = f1(s,1,4) return ((c1 * 64 + c2) * 64 + c3) * 64 + c4 - 63447168 end
+--~ lpeg.print(lpeg.R("ab","cd","gh"))
+--~ lpeg.print(lpeg.P("a","b","c"))
+--~ lpeg.print(lpeg.S("a","b","c"))
 
-patterns.utf8byte = patterns.utf8one/f1 + patterns.utf8two/f2 + patterns.utf8three/f3 + patterns.utf8four/f4
+--~ print(lpeg.count("äáàa",lpeg.P("á") + lpeg.P("à")))
+--~ print(lpeg.count("äáàa",lpeg.UP("áà")))
+--~ print(lpeg.count("äáàa",lpeg.US("àá")))
+--~ print(lpeg.count("äáàa",lpeg.UR("aá")))
+--~ print(lpeg.count("äáàa",lpeg.UR("àá")))
+--~ print(lpeg.count("äáàa",lpeg.UR(0x0000,0xFFFF)))
+
+function lpeg.is_lpeg(p)
+    return p and lpegtype(p) == "pattern"
+end
+
+function lpeg.oneof(list,...) -- lpeg.oneof("elseif","else","if","then") -- assume proper order
+    if type(list) ~= "table" then
+        list = { list, ... }
+    end
+ -- table.sort(list) -- longest match first
+    local p = P(list[1])
+    for l=2,#list do
+        p = p + P(list[l])
+    end
+    return p
+end
+
+-- For the moment here, but it might move to utilities. Beware, we need to
+-- have the longest keyword first, so 'aaa' comes beforte 'aa' which is why we
+-- loop back from the end cq. prepend.
+
+local sort, fastcopy, sortedkeys = table.sort, table.fastcopy, table.sortedkeys -- dependency!
+
+function lpeg.append(list,pp,delayed,checked)
+    local p = pp
+    if #list > 0 then
+        local keys = fastcopy(list)
+        sort(keys)
+        for i=#keys,1,-1 do
+            local k = keys[i]
+            if p then
+                p = P(k) + p
+            else
+                p = P(k)
+            end
+        end
+    elseif delayed then -- hm, it looks like the lpeg parser resolves anyway
+        local keys = sortedkeys(list)
+        if p then
+            for i=1,#keys,1 do
+                local k = keys[i]
+                local v = list[k]
+                p = P(k)/list + p
+            end
+        else
+            for i=1,#keys do
+                local k = keys[i]
+                local v = list[k]
+                if p then
+                    p = P(k) + p
+                else
+                    p = P(k)
+                end
+            end
+            if p then
+                p = p / list
+            end
+        end
+    elseif checked then
+        -- problem: substitution gives a capture
+        local keys = sortedkeys(list)
+        for i=1,#keys do
+            local k = keys[i]
+            local v = list[k]
+            if p then
+                if k == v then
+                    p = P(k) + p
+                else
+                    p = P(k)/v + p
+                end
+            else
+                if k == v then
+                    p = P(k)
+                else
+                    p = P(k)/v
+                end
+            end
+        end
+    else
+        local keys = sortedkeys(list)
+        for i=1,#keys do
+            local k = keys[i]
+            local v = list[k]
+            if p then
+                p = P(k)/v + p
+            else
+                p = P(k)/v
+            end
+        end
+    end
+    return p
+end
+
+-- inspect(lpeg.append({ a = "1", aa = "1", aaa = "1" } ,nil,true))
+-- inspect(lpeg.append({ ["degree celsius"] = "1", celsius = "1", degree = "1" } ,nil,true))
+
+-- function lpeg.exact_match(words,case_insensitive)
+--     local pattern = concat(words)
+--     if case_insensitive then
+--         local pattern = S(upper(characters)) + S(lower(characters))
+--         local list = { }
+--         for i=1,#words do
+--             list[lower(words[i])] = true
+--         end
+--         return Cmt(pattern^1, function(_,i,s)
+--             return list[lower(s)] and i
+--         end)
+--     else
+--         local pattern = S(concat(words))
+--         local list = { }
+--         for i=1,#words do
+--             list[words[i]] = true
+--         end
+--         return Cmt(pattern^1, function(_,i,s)
+--             return list[s] and i
+--         end)
+--     end
+-- end
+
+-- experiment:
+
+local function make(t)
+    local p
+--     for k, v in next, t do
+    for k, v in table.sortedhash(t) do
+        if not p then
+            if next(v) then
+                p = P(k) * make(v)
+            else
+                p = P(k)
+            end
+        else
+            if next(v) then
+                p = p + P(k) * make(v)
+            else
+                p = p + P(k)
+            end
+        end
+    end
+    return p
+end
+
+function lpeg.utfchartabletopattern(list)
+    local tree = { }
+    for i=1,#list do
+        local t = tree
+        for c in gmatch(list[i],".") do
+            if not t[c] then
+                t[c] = { }
+            end
+            t = t[c]
+        end
+    end
+    return make(tree)
+end
+
+-- inspect ( lpeg.utfchartabletopattern {
+--     utfchar(0x00A0), -- nbsp
+--     utfchar(0x2000), -- enquad
+--     utfchar(0x2001), -- emquad
+--     utfchar(0x2002), -- enspace
+--     utfchar(0x2003), -- emspace
+--     utfchar(0x2004), -- threeperemspace
+--     utfchar(0x2005), -- fourperemspace
+--     utfchar(0x2006), -- sixperemspace
+--     utfchar(0x2007), -- figurespace
+--     utfchar(0x2008), -- punctuationspace
+--     utfchar(0x2009), -- breakablethinspace
+--     utfchar(0x200A), -- hairspace
+--     utfchar(0x200B), -- zerowidthspace
+--     utfchar(0x202F), -- narrownobreakspace
+--     utfchar(0x205F), -- math thinspace
+-- } )
+
+-- handy from within tex:
+
+local lpegmatch = lpeg.match
+
+local replacer = lpeg.replacer("@","%%") -- Watch the escaped % in lpeg!
+
+function string.tformat(fmt,...)
+    return format(lpegmatch(replacer,fmt),...)
+end
+
+-- strips leading and trailing spaces and collapsed all other spaces
+
+local pattern = Cs(whitespace^0/"" * ((whitespace^1 * P(-1) / "") + (whitespace^1/" ") + P(1))^0)
+
+function string.collapsespaces(str)
+    return lpegmatch(pattern,str)
+end