Mô đun:If preview/configuration

--[[We perform the actual check for whether this is a preview here sincepreprocessing is relatively expensive.]]local frame = mw.getCurrentFrame()local function is_preview()	local revision_id = frame:preprocess('{{REVISIONID}}')	-- {{REVISIONID}} is usually the empty string when previewed.	-- I don't know why we're checking for nil but hey, maybe someday things	-- would have broken	return revision_id == nil or revision_id == ''endlocal function templatestyles()	return frame:extensionTag{		name = 'templatestyles', args = { src = 'Module:If preview/styles.css' }	}endreturn {	preview = is_preview(),	templatestyles = templatestyles(),	warning_infrastructure = '%s<div class="preview-warning"><strong>Cảnh báo xem trước:</strong> %s</div>',	missing_warning = 'The template has no warning text. Please add a warning.'}