public readonly struct angle180

{

    readonly float _val, _raw;

​

    public angle180( float angle )

    {

        if( float.IsInfinity( angle ) ) throw new System.ArgumentException("Input value must be finite", "angle");

        if( float.IsNaN( angle ) ) throw new System.ArgumentException("Input value must not be NaN", "angle");

​

        _val = _raw = angle;

​

        while( _val < -180 ) _val += 360;

        while( _val > 180 ) _val -= 360;

    }

​

    public float val { get { return _val; } }

    public float raw { get { return _raw; } }

​

    public override string ToString() => _val.ToString();

​

    // angle180 & angle180

    public static angle180 operator +(angle180 a) => a;

    public static angle180 operator -(angle180 a) => new angle180( - a.val );

    public static angle180 operator +(angle180 lhs, angle180 rhs) => new angle180( lhs.val + rhs.val );

    public static angle180 operator *(angle180 lhs, angle180 rhs) => new angle180( lhs.val * rhs.val );

    public static angle180 operator /(angle180 lhs, angle180 rhs) {

        if (rhs.val == 0) throw new System.DivideByZeroException();

        return new angle180( lhs.val / rhs.val ); }

​

    // float & angle180

    public static implicit operator angle180(float rhs) => new angle180( rhs );

    public static implicit operator float(angle180 rhs) => rhs.val;

​

    public static float operator +(float lhs, angle180 rhs) => ( new angle180( lhs + rhs.val ) ).val;

    public static float operator +(angle180 lhs, float rhs) => ( new angle180( lhs.val + rhs ) ).val;       

    public static float operator -(float lhs, angle180 rhs) => ( new angle180( lhs - rhs.val ) ).val;

    public static float operator -(angle180 lhs, float rhs) => ( new angle180( lhs.val - rhs ) ).val;       

    public static float operator *(float lhs, angle180 rhs) => ( new angle180( lhs * rhs.val ) ).val;

    public static float operator *(angle180 lhs, float rhs) => ( new angle180( lhs.val * rhs ) ).val;       

    public static float operator /(float lhs, angle180 rhs) { 

        if (rhs.val == 0) throw new System.DivideByZeroException();

        return ( new angle180( lhs / rhs.val ) ).val; }

    public static float operator /(angle180 lhs, float rhs) { 

        if (rhs  == 0) throw new System.DivideByZeroException();

        return ( new angle180( lhs.val / rhs ) ).val; }

}