Module:Convert

Documentation for this module may be created at Module:Convert/doc

--require "mw.text"
--require "mw.page"

-- TODO: lots of things still need doing but below are a few of the major bits
--       Support for numeric precision
--       Support for all the different conversion units

local p = {}

function convert(in_val,in_unit,out_unit)
    local out_val;
    local units = in_unit .. "|" .. out_unit
    if units == "°C|°F" or units == "C|F" then
        out_val = in_val * 9 / 5 + 32;
    elseif units == "°F|°C" or units == "F|C" then
        out_val = (in_val - 32) * 5 / 9;
    elseif units == "kg|lb" then
        out_val = in_val * 2.20462262;
    elseif units == "lb|kg" then
        out_val = in_val / 2.20462262;
    elseif units == "km|mi" then
        out_val = in_val * 0.621371192;
    elseif units == "mi|km" then
        out_val = in_val / 0.621371192;
    elseif units == "km2|sqmi" then
        out_val = in_val * 0.621371192^2;
    elseif units == "sqmi|2km" then
        out_val = in_val / 0.621371192^2;
    else
        error ("Module:Converting between " .. in_unit .. " and " .. out_unit .. " not supported.");
    end
    return out_val
end


-- This is the top-level function called by {{convert}}.
function p.main(frame, config, args)
    local pframe = frame:getParent();
    local args = pframe.args; -- the arguments passed TO the {{convert}} template, in the wikitext that instantiates the template
    local config = frame.args; -- the arguments passed BY the {{convert}} template, in the wikitext of the template itself
    local output;
    
    in_val1 = tonumber(args[1]);
    in_val2 = tonumber(args[3]);
    disp = args["disp"];

    if in_val1 == nil then
        error ("Module:Convert value not supplied");
        return ""
    end

    if in_val2 == nil then
        -- Single value supplied
        in_unit  = args[2];
        out_unit = args[3];
        out_val1 = convert(in_val1,in_unit,out_unit);
        
        if disp == "or" then
            output = in_val1 .. " " .. in_unit .. " or " .. out_val1 .. " " .. out_unit;
        elseif disp == "sqbr" then
            output = in_val1 .. " " .. in_unit .. " <nowiki>[</nowiki>" .. out_val1 .. " " .. out_unit .. "<nowiki>]</nowiki>";
        else
            output = in_val1 .. " " .. in_unit .. " (" .. out_val1 .. " " .. out_unit .. ")";
        end
    else
        -- Two values supplied
        range    = args[2];
        in_unit  = args[4];
        out_unit = args[5];
        out_val1 = convert(in_val1,in_unit,out_unit);
        out_val2 = convert(in_val2,in_unit,out_unit);

        output = in_val1 .. " " .. range .. " " .. in_val2 .. " " .. in_unit .. " (" .. out_val1 .. " " .. range .. " " .. out_val2 .. " " .. out_unit .. ")";
    end
    
    --error ("Module:Convert is not implemented");
    return output    
end

return p