if not modules then modules = { } end modules ['meta-ini'] = {
    version   = 1.001,
    comment   = "companion to meta-ini.mkiv",
    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
    copyright = "PRAGMA ADE / ConTeXt Development Team",
    license   = "see context related readme files"
}

local tonumber = tonumber
local format = string.format
local lpegmatch, lpegpatterns = lpeg.match, lpeg.patterns
local P, Cs, R, S, C, Cc = lpeg.P, lpeg.Cs, lpeg.R, lpeg.S, lpeg.C, lpeg.Cc

local context = context

metapost = metapost or { }

-- experimental

local colorhash = attributes.list[attributes.private('color')]

local textype   = tex.type
local MPcolor   = context.MPcolor

-- local validdimen = lpegpatterns.validdimen * P(-1)
--
-- function commands.prepareMPvariable(v) -- slow but ok
--     if v == "" then
--         MPcolor("black")
--     else
--         local typ, var = match(v,"(.):(.*)")
--         if not typ then
--             -- parse
--             if colorhash[v] then
--                 MPcolor(v)
--             elseif tonumber(v) then
--                 context(v)
--             elseif lpegmatch(validdimen,v) then
--                 return context("\\the\\dimexpr %s",v)
--             else
--                 for s in gmatch(v,"\\([a-zA-Z]+)") do -- can have trailing space
--                     local t = textype(s)
--                     if t == "dimen" then
--                         return context("\\the\\dimexpr %s",v)
--                     elseif t == "count" then
--                         return context("\\the\\numexpr %s",v)
--                     end
--                 end
--                 context("\\number %s",v) -- 0.4 ...
--             end
--         elseif typ == "d" then -- to be documented
--             -- dimension
--             context("\\the\\dimexpr %s",var)
--         elseif typ == "n" then -- to be documented
--             -- number
--             context("\\the\\numexpr %s",var)
--         elseif typ == "s" then -- to be documented
--             -- string
--             context(var)
--         elseif typ == "c" then -- to be documented
--             -- color
--             MPcolor(var)
--         else
--             context(var)
--         end
--     end
-- end

-- we can actually get the dimen/count values here

local dimenorname  =
    lpegpatterns.validdimen / function(s)
        context("\\the\\dimexpr %s",s)
    end
  + (C(lpegpatterns.float) + Cc(1)) * lpegpatterns.space^0 * P("\\") * C(lpegpatterns.letter^1) / function(f,s)
        local t = textype(s)
        if t == "dimen" then
            context("\\the\\dimexpr %s\\%s\\relax",f,s)
        elseif t == "count" then
            context("\\the\\numexpr \\%s * %s\\relax",s,f) -- <n>\scratchcounter is not permitted
        end
    end

local splitter = lpeg.splitat("::",true)

interfaces.implement {
    name      = "prepareMPvariable",
    arguments = "string",
    actions   = function(v)
        if v == "" then
         -- MPcolor("black")
            context("black")
        else
            local typ, var = lpegmatch(splitter,v)
            if not var then
                -- parse
                if colorhash[v] then
                 -- MPcolor(v)
                    context("%q",var)
                elseif tonumber(v) then
                    context(v)
                elseif not lpegmatch(dimenorname,v) then
                    context("\\number %s",v) -- 0.4 ...
                end
            elseif typ == "d" then -- to be documented
                -- dimension
                context("\\the\\dimexpr %s\\relax",var)
            elseif typ == "n" then -- to be documented
                -- number
                context("\\the\\numexpr %s\\relax",var)
            elseif typ == "s" then -- to be documented
                -- string
             -- context(var)
                context("%q",var)
            elseif typ == "c" then -- to be documented
                -- color
             -- MPcolor(var)
                context("%q",var)
            else
                context(var)
            end
        end
    end
}

-- function metapost.formatnumber(f,n) -- just lua format
--     f = gsub(f,"@(%d)","%%.%1")
--     f = gsub(f,"@","%%")
--     f = format(f,tonumber(n) or 0)
--     f = gsub(f,"e([%+%-%d]+)",function(s)
--         return format("\\times10^{%s}",tonumber(s) or s) -- strips leading zeros
--     end)
--     context.mathematics(f)
-- end

-- formatters["\\times10^{%N}"](s) -- strips leading zeros too

local one = Cs((P("@")/"%%." * (R("09")^1) + P("@")/"%%" + 1)^0)
local two = Cs((P("e")/"" * ((S("+-")^0 * R("09")^1) / function(s) return format("\\times10^{%s}",tonumber(s) or s) end) + 1)^1)

-- local two = Cs((P("e")/"" * ((S("+-")^0 * R("09")^1) / formatters["\\times10^{%N}"]) + 1)^1)

function metapost.formatnumber(fmt,n) -- just lua format
    context.mathematics(lpegmatch(two,format(lpegmatch(one,fmt),n)))
end
