def check_positive(value, strict=False):
    """
    Checks if variable is positive

    @param value: value to check
    @type value: C{integer types}, C{float} or C{Decimal}

    @return: None when check successful

    @raise ValueError: check failed
    """
    if not strict and value < 0:
        raise ValueError('Value must be positive or zero, not %s' % str(value))
    if strict and value <= 0:
        raise ValueError('Value must be positive, not %s' % str(value))
