Function ExampleOption_transformComplex

cmp/example_test.go:264–304

The complex numbers complex64 and complex128 can really just be decomposed into a pair of float32 or float64 values. It would be convenient to be able define only a single comparator on float64 and have float32, complex64, and complex128 all be able to use that comparator. Transformations can be use

()

// complex128 all be able to use that comparator. Transformations can be used
// to handle this.
func ExampleOption_transformComplex() {
	opts := []cmp.Option{
		// This transformer decomposes complex128 into a pair of float64s.
		cmp.Transformer("T1", func(in complex128) (out struct{ Real, Imag float64 }) {
			out.Real, out.Imag = real(in), imag(in)
			return out
		}),
		// This transformer converts complex64 to complex128 to allow the
		// above transform to take effect.
		cmp.Transformer("T2", func(in complex64) complex128 {
			return complex128(in)
		}),
		// This transformer converts float32 to float64.
		cmp.Transformer("T3", func(in float32) float64 {
			return float64(in)
		}),
		// This equality function compares float64s as rounded integers.
		cmp.Comparer(func(x, y float64) bool {
			return roundF64(x) == roundF64(y)
		}),
	}

	x := []interface{}{
		complex128(3.0), complex64(5.1 + 2.9i), float32(-1.2), float64(12.3),
	}
	y := []interface{}{
		complex128(3.1), complex64(4.9 + 3.1i), float32(-1.3), float64(11.7),
	}
	z := []interface{}{
		complex128(3.8), complex64(4.9 + 3.1i), float32(-1.3), float64(11.7),
	}

	fmt.Println(cmp.Equal(x, y, opts...))
	fmt.Println(cmp.Equal(y, z, opts...))
	fmt.Println(cmp.Equal(z, x, opts...))

	// Output:
	// true
	// false
	// false
}

type (
	Gateway struct {