def iterFields(fields, properties_tab):
    for (name, tp, idx) in properties_tab:
        val = fields[idx]
        if (val == '.'):
            (yield (name, None))
        else:
            (yield (name, tp(val)))
def iterFields(fields, properties_tab):
    for (name, tp, idx) in properties_tab:
        val = fields[idx]
        if (val == '.'):
            (yield (name, None))
        else:
            (yield (name, tp(val)))