proc get_widgets {{start_path .}} {
	global widgets
	if {[string equal $start_path .]} {
		catch {unset widgets}
	}
	set ws [winfo children $start_path]
	add_widget $ws
	foreach w $ws {
		add_widget $w
		get_widgets $w
	}
}

proc add_widget {w} {
	if {[winfo exist $w]} {
		upvar #0 widgets([winfo class $w]) type
		lappend type $w
	}
}

proc new_config {cl ncfg val {map "*"}} {
	global widgets
	foreach widg $widgets($cl) {
		if {[string match $map $widg]} {
			$widg configure $ncfg $val
			option add $map.[lindex [$widg configure $ncfg] 2] $val
		}
	}
}

get_widgets
new_config Button -background green *tastebin*