Module:Age: Difference between revisions

    (implement age in years and months; could readily extend for other similar functions)
     
    (add support for {{Age in days}} and {{Gregorian serial date}})
    Line 1: Line 1:
    -- Code to implement {{age in years and months}}.
    --[[ Code for some date functions, including implementations of:
    -- This could be extended to handle the many other {{age}} templates.
            {{Age in days}}                age_days
    -- However, calendar functions will be needed in many areas, so this may be
            {{Age in years and months}}     age_ym
    -- superseded by some other system, perhaps using functions from the PHP host.
            {{Gregorian serial date}}       gsd_ymd
    Calendar functions will be needed in many areas, so this may be superseded
    by some other system, perhaps using PHP functions accessed via mw.
    ]]


    local MINUS = '−'  -- Unicode U+2212 MINUS SIGN (UTF-8: e2 88 92)
    local MINUS = '−'  -- Unicode U+2212 MINUS SIGN


    local function number_name(number, singular, plural, sep)
    local function number_name(number, singular, plural, sep)
        -- Return the given number, converted to a string, with the
        -- separator (default space) and singular or plural name appended.
         plural = plural or (singular .. 's')
         plural = plural or (singular .. 's')
         sep = sep or ' '
         sep = sep or ' '
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    end
    end


    local function strip(text)
    local function strip_to_nil(text)
         -- If text is a string, return its content with no leading/trailing
         -- If text is a non-blank string, return its content with no leading
         -- whitespace. Otherwise return nil (a nil argument gives a nil result).
         -- or trailing whitespace.
        -- Otherwise return nil (a nil or empty string argument gives a nil
        -- result, as does a string argument of only whitespace).
         if type(text) == 'string' then
         if type(text) == 'string' then
             return text:match("^%s*(.-)%s*$")
             local result = text:match("^%s*(.-)%s*$")
            if result ~= '' then
                return result
            end
         end
         end
        return nil
    end
    end


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         end
         end
         return month_days[month]
         return month_days[month]
    end
    -- A table to get current year/month/day (UTC), but only if needed.
    local current = setmetatable({}, {
            __index = function (self, key)
                local d = os.date('!*t')
                self.year = d.year
                self.month = d.month
                self.day = d.day
                return rawget(self, key)
            end
        })
    local function date_component(named, positional, component)
        -- Return the first of the two arguments that is not nil and is not empty.
        -- If both are nil, return the current date component, if specified.
        -- The returned value is nil or is a number.
        -- This translates empty arguments passed to the template to nil, and
        -- optionally replaces a nil argument with a value from the current date.
        named = strip_to_nil(named)
        if named then
            return tonumber(named)
        end
        positional = strip_to_nil(positional)
        if positional then
            return tonumber(positional)
        end
        if component then
            return current[component]
        end
        return nil
    end
    local function gsd(year, month, day)
        -- Return the Gregorian serial day (an integer >= 1) for the given date,
        -- or return nil if the date is invalid (only check that year >= 1).
        -- This is the number of days from the start of 1 AD (there is no year 0).
        -- This code implements the logic in [[Template:Gregorian serial date]].
        if year < 1 then
            return nil
        end
        local floor = math.floor
        local days_this_year = (month - 1) * 30.5 + day
        if month > 2 then
            if is_leap_year(year) then
                days_this_year = days_this_year - 1
            else
                days_this_year = days_this_year - 2
            end
            if month > 8 then
                days_this_year = days_this_year + 0.9
            end
        end
        days_this_year = floor(days_this_year + 0.5)
        year = year - 1
        local days_from_past_years = year * 365
            + floor(year / 4)
            - floor(year / 100)
            + floor(year / 400)
        return days_from_past_years + days_this_year
    end
    end


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         end
         end
    }
    }
    function Date:__lt(rhs)
        -- Return true if self < rhs.
        if self.year < rhs.year then
            return true
        end
        if self.year == rhs.year then
            if self.month < rhs.month then
                return true
            end
            if self.month == rhs.month then
                return self.day < rhs.day
            end
        end
        return false
    end


    function Date:set_current()
    function Date:set_current()
         -- Set date from current time (UTC) and return self.
         -- Set date from current time (UTC) and return self.
        local d = os.date('!*t')
         self.year = current.year
         self.year = d.year
         self.month = current.month
         self.month = d.month
         self.day = current.day
         self.day = d.day
         self.isvalid = true
         self.isvalid = true
         return self
         return self
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         end
         end
         return self
         return self
    end
    function Date:less_than(rhs)
        -- Set true if self < rhs.
        if self.year < rhs.year then
            return true
        end
        if self.year == rhs.year then
            if self.month < rhs.month then
                return true
            end
            if self.month == rhs.month then
                return self.day < rhs.day
            end
        end
        return false
    end
    end


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         -- Difference is negative if the second date is older than the first.
         -- Difference is negative if the second date is older than the first.
         local isnegative
         local isnegative
         if date2:less_than(date1) then
         if date2 < date1 then
             isnegative = true
             isnegative = true
             date1, date2 = date2, date1
             date1, date2 = date2, date1
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    local function error_wikitext(text)
    local function error_wikitext(text)
         -- Return message for display when template parameters are invalid.
         -- Return message for display when template parameters are invalid.
        -- TODO Get opinions on whether the prefix and category are suitable.
         local prefix = '[[Module talk:Age|Module error]]:'
         local prefix = '[[Module talk:Age|Module error]]:'
         local cat = '[[Category:Age error]]'
         local cat = '[[Category:Age error]]'
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    end
    end


    local function get_parms(pframe)
    local function age_days(frame)
         -- Return date1, date2 from parameters to template.
         -- Return age in days between two given dates, or
         -- If date1 is missing or invalid, the returned date1 is nil.
        -- between given date and current date.
         -- If date2 is missing, the returned date2 is the current date.
         -- This code implements the logic in [[Template:Age in days]].
         -- If date2 is invalid, the returned date2 is nil.
         -- Like {{Age in days}}, a missing argument is replaced from the current
         local args = {} -- arguments passed to template
        -- date, so can get a bizarre mixture of specified/current y/m/d.
        local args = frame:getParent().args
        local year1  = date_component(args.year1 , args[1], 'year' )
        local month1 = date_component(args.month1, args[2], 'month')
        local day1  = date_component(args.day1  , args[3], 'day'  )
        local year2  = date_component(args.year2 , args[4], 'year' )
         local month2 = date_component(args.month2, args[5], 'month')
        local day2  = date_component(args.day2  , args[6], 'day'  )
        local gsd1 = gsd(year1, month1, day1)
        local gsd2 = gsd(year2, month2, day2)
        if gsd1 and gsd2 then
            local sign = ''
            local result = gsd2 - gsd1
            if result < 0 then
                sign = MINUS
                result = -result
            end
            return sign .. tostring(result)
        end
        return error_wikitext('Cannot handle dates before the year 1 AD')
    end
     
    local function age_ym(frame)
        -- Return age in years and months between two given dates, or
        -- between given date and current date.
         local args = frame:getParent().args
        local fields = {}
         for i = 1, 6 do
         for i = 1, 6 do
             args[i] = strip(pframe.args[i])
             fields[i] = strip_to_nil(args[i])
         end
         end
         local date1, date2
         local date1, date2
         if args[1] and args[2] and args[3] then
         if fields[1] and fields[2] and fields[3] then
             date1 = Date:new():set_ymd(args[1], args[2], args[3])
             date1 = Date:new():set_ymd(fields[1], fields[2], fields[3])
            if not date1.isvalid then
        end
                date1 = nil
        if not (date1 and date1.isvalid) then
             end
             return error_wikitext('Need date: year, month, day')
         end
         end
         if args[4] and args[5] and args[6] then
         if fields[4] and fields[5] and fields[6] then
             date2 = Date:new():set_ymd(args[4], args[5], args[6])
             date2 = Date:new():set_ymd(fields[4], fields[5], fields[6])
             if not date2.isvalid then
             if not date2.isvalid then
                 date2 = nil
                 return error_wikitext('Second date should be year, month, day')
             end
             end
         else
         else
             date2 = Date:new():set_current()
             date2 = Date:new():set_current()
         end
         end
         return date1, date2
         return DateDiff:new():set(date1, date2):age_ym()
    end
    end


    local function age_ym(frame)
    local function gsd_ymd(frame)
         local date1, date2 = get_parms(frame:getParent())
        -- Return Gregorian serial day of the given date, or the current date.
         if date1 then
        -- Like {{Gregorian serial date}}, a missing argument is replaced from the
            if not date2 then
        -- current date, so can get a bizarre mixture of specified/current y/m/d.
                return error_wikitext('Second date should be year, month, day')
        -- This accepts positional arguments, although the original template does not.
            end
         local args = frame:getParent().args
            local diff = DateDiff:new():set(date1, date2)
         local year  = date_component(args.year , args[1], 'year' )
             return diff:age_ym()
        local month = date_component(args.month, args[2], 'month')
        local day  = date_component(args.day  , args[3], 'day' )
        local result = gsd(year, month, day)
        if result then
             return tostring(result)
         end
         end
         return error_wikitext('Need date: year, month, day')
         return error_wikitext('Cannot handle dates before the year 1 AD')
    end
    end


    return { age_ym = age_ym }
    return { age_days = age_days, age_ym = age_ym, gsd = gsd_ymd }
    Retrieved from "https://nonbinary.wiki/wiki/Module:Age"