Module:Utils

Documentation for this module may be created at ModuleDoc:Utils

local utils = {}

function utils.tableEmpty( tab )
	return next( tab ) == nil
end

function utils.defaultIfEmpty( val, default )
	if val == nil or val == '' or ( type( val ) == 'table' and utils.tableEmpty( val ) ) then
		return default
	else
		return val
	end
end

function utils.loadDataIfExists( name )
	local success, data = pcall( mw.loadData, name )
	if success then
		return data
	else
		return nil
	end
end

function utils.error( ... )
	-- Collect necessary information to display error
	local message = tostring( utils.defaultIfEmpty( select( 1, ... ), 'There was an error with a template. Are the parameters all correct?' ) )
	local etype = tostring( utils.defaultIfEmpty( select( 2, ... ), 'Template' ) )
	local category = tostring( utils.defaultIfEmpty( select( 3, ... ), 'Pages containing template errors' ) )
	local template = utils.defaultIfEmpty( select( 4, ... ), nil )
	
	-- Style data 
	etype = string.upper( etype )
	
	-- Add a warning to the edit preview
	if template == nil then
		mw.addWarning( "'''" .. etype .. " ERROR:''' " .. message )
	else
		mw.addWarning( "'''" .. etype .. " ERROR:''' " .. message .. ' (Template name: "' .. tostring( template ) .. '")' )
	end
	
	-- Create and return the text to display on the page itself
	return [[<span class="template-error" style="color: red;">''']]
		.. etype
		.. [[ ERROR:''' ]]
		.. message
		.. '</span> [[Category:'
		.. category
		.. ']]'
end

return utils