Expand pgtype.Value interface

- Include and rename ConvertFrom to Set
- Add Get
- Include AssignTo

pgtype/aclitem.go

@@ -23,7 +23,7 @@ type Aclitem struct {
 	Status Status
 }
 
-func (dst *Aclitem) ConvertFrom(src interface{}) error {
+func (dst *Aclitem) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Aclitem:
 		*dst = value
@@ -37,7 +37,7 @@ func (dst *Aclitem) ConvertFrom(src interface{}) error {
 		}
 	default:
 		if originalSrc, ok := underlyingStringType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Aclitem", value)
 	}
@@ -45,6 +45,17 @@ func (dst *Aclitem) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Aclitem) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.String
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Aclitem) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *string:

pgtype/aclitem_array.go

@@ -14,7 +14,7 @@ type AclitemArray struct {
 	Status     Status
 }
 
-func (dst *AclitemArray) ConvertFrom(src interface{}) error {
+func (dst *AclitemArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case AclitemArray:
 		*dst = value
@@ -27,7 +27,7 @@ func (dst *AclitemArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Aclitem, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -40,7 +40,7 @@ func (dst *AclitemArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Aclitem", value)
 	}
@@ -48,6 +48,17 @@ func (dst *AclitemArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *AclitemArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *AclitemArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/aclitem_array_test.go

@@ -51,7 +51,7 @@ func TestAclitemArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestAclitemArrayConvertFrom(t *testing.T) {
+func TestAclitemArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.AclitemArray
@@ -71,7 +71,7 @@ func TestAclitemArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.AclitemArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/aclitem_test.go

@@ -15,7 +15,7 @@ func TestAclitemTranscode(t *testing.T) {
 	})
 }
 
-func TestAclitemConvertFrom(t *testing.T) {
+func TestAclitemSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Aclitem
@@ -27,7 +27,7 @@ func TestAclitemConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var d pgtype.Aclitem
-		err := d.ConvertFrom(tt.source)
+		err := d.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/bool.go

@@ -12,7 +12,7 @@ type Bool struct {
 	Status Status
 }
 
-func (dst *Bool) ConvertFrom(src interface{}) error {
+func (dst *Bool) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Bool:
 		*dst = value
@@ -26,7 +26,7 @@ func (dst *Bool) ConvertFrom(src interface{}) error {
 		*dst = Bool{Bool: bb, Status: Present}
 	default:
 		if originalSrc, ok := underlyingBoolType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Bool", value)
 	}
@@ -34,6 +34,17 @@ func (dst *Bool) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Bool) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Bool
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Bool) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *bool:

pgtype/bool_array.go

@@ -15,7 +15,7 @@ type BoolArray struct {
 	Status     Status
 }
 
-func (dst *BoolArray) ConvertFrom(src interface{}) error {
+func (dst *BoolArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case BoolArray:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *BoolArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Bool, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -41,7 +41,7 @@ func (dst *BoolArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Bool", value)
 	}
@@ -49,6 +49,17 @@ func (dst *BoolArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *BoolArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *BoolArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/bool_array_test.go

@@ -51,7 +51,7 @@ func TestBoolArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestBoolArrayConvertFrom(t *testing.T) {
+func TestBoolArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.BoolArray
@@ -71,7 +71,7 @@ func TestBoolArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.BoolArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/bool_test.go

@@ -15,7 +15,7 @@ func TestBoolTranscode(t *testing.T) {
 	})
 }
 
-func TestBoolConvertFrom(t *testing.T) {
+func TestBoolSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Bool
@@ -33,7 +33,7 @@ func TestBoolConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Bool
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/bytea.go

@@ -12,7 +12,7 @@ type Bytea struct {
 	Status Status
 }
 
-func (dst *Bytea) ConvertFrom(src interface{}) error {
+func (dst *Bytea) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Bytea:
 		*dst = value
@@ -24,7 +24,7 @@ func (dst *Bytea) ConvertFrom(src interface{}) error {
 		}
 	default:
 		if originalSrc, ok := underlyingBytesType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Bytea", value)
 	}
@@ -32,6 +32,17 @@ func (dst *Bytea) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Bytea) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Bytes
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Bytea) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *[]byte:

pgtype/bytea_array.go

@@ -15,7 +15,7 @@ type ByteaArray struct {
 	Status     Status
 }
 
-func (dst *ByteaArray) ConvertFrom(src interface{}) error {
+func (dst *ByteaArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case ByteaArray:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *ByteaArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Bytea, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -41,7 +41,7 @@ func (dst *ByteaArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Bytea", value)
 	}
@@ -49,6 +49,17 @@ func (dst *ByteaArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *ByteaArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *ByteaArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/bytea_array_test.go

@@ -51,7 +51,7 @@ func TestByteaArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestByteaArrayConvertFrom(t *testing.T) {
+func TestByteaArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.ByteaArray
@@ -71,7 +71,7 @@ func TestByteaArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.ByteaArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/bytea_test.go

@@ -15,7 +15,7 @@ func TestByteaTranscode(t *testing.T) {
 	})
 }
 
-func TestByteaConvertFrom(t *testing.T) {
+func TestByteaSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Bytea
@@ -30,7 +30,7 @@ func TestByteaConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Bytea
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/cid.go

@@ -17,11 +17,15 @@ import (
 // in the PostgreSQL sources.
 type Cid pguint32
 
-// ConvertFrom converts from src to dst. Note that as Cid is not a general
+// Set converts from src to dst. Note that as Cid is not a general
-// number type ConvertFrom does not do automatic type conversion as other number
+// number type Set does not do automatic type conversion as other number
 // types do.
-func (dst *Cid) ConvertFrom(src interface{}) error {
+func (dst *Cid) Set(src interface{}) error {
-	return (*pguint32)(dst).ConvertFrom(src)
+	return (*pguint32)(dst).Set(src)
+}
+
+func (dst *Cid) Get() interface{} {
+	return (*pguint32)(dst).Get()
 }
 
 // AssignTo assigns from src to dst. Note that as Cid is not a general number

pgtype/cid_test.go

@@ -14,7 +14,7 @@ func TestCidTranscode(t *testing.T) {
 	})
 }
 
-func TestCidConvertFrom(t *testing.T) {
+func TestCidSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Cid
@@ -24,7 +24,7 @@ func TestCidConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Cid
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/cidr_array.go

@@ -6,8 +6,12 @@ import (
 
 type CidrArray InetArray
 
-func (dst *CidrArray) ConvertFrom(src interface{}) error {
+func (dst *CidrArray) Set(src interface{}) error {
-	return (*InetArray)(dst).ConvertFrom(src)
+	return (*InetArray)(dst).Set(src)
+}
+
+func (dst *CidrArray) Get() interface{} {
+	return (*InetArray)(dst).Get()
 }
 
 func (src *CidrArray) AssignTo(dst interface{}) error {

pgtype/date.go

@@ -21,7 +21,7 @@ const (
 	infinityDayOffset         = 2147483647
 )
 
-func (dst *Date) ConvertFrom(src interface{}) error {
+func (dst *Date) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Date:
 		*dst = value
@@ -29,7 +29,7 @@ func (dst *Date) ConvertFrom(src interface{}) error {
 		*dst = Date{Time: value, Status: Present}
 	default:
 		if originalSrc, ok := underlyingTimeType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Date", value)
 	}
@@ -37,6 +37,17 @@ func (dst *Date) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Date) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Time
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Date) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *time.Time:

pgtype/date_array.go

@@ -16,7 +16,7 @@ type DateArray struct {
 	Status     Status
 }
 
-func (dst *DateArray) ConvertFrom(src interface{}) error {
+func (dst *DateArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case DateArray:
 		*dst = value
@@ -29,7 +29,7 @@ func (dst *DateArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Date, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -42,7 +42,7 @@ func (dst *DateArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Date", value)
 	}
@@ -50,6 +50,17 @@ func (dst *DateArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *DateArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *DateArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/date_array_test.go

@@ -52,7 +52,7 @@ func TestDateArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestDateArrayConvertFrom(t *testing.T) {
+func TestDateArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.DateArray
@@ -72,7 +72,7 @@ func TestDateArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.DateArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/date_test.go

@@ -22,7 +22,7 @@ func TestDateTranscode(t *testing.T) {
 	})
 }
 
-func TestDateConvertFrom(t *testing.T) {
+func TestDateSet(t *testing.T) {
 	type _time time.Time
 
 	successfulTests := []struct {
@@ -41,7 +41,7 @@ func TestDateConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var d pgtype.Date
-		err := d.ConvertFrom(tt.source)
+		err := d.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/float4.go

@@ -15,7 +15,7 @@ type Float4 struct {
 	Status Status
 }
 
-func (dst *Float4) ConvertFrom(src interface{}) error {
+func (dst *Float4) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Float4:
 		*dst = value
@@ -81,7 +81,7 @@ func (dst *Float4) ConvertFrom(src interface{}) error {
 		*dst = Float4{Float: float32(num), Status: Present}
 	default:
 		if originalSrc, ok := underlyingNumberType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Float8", value)
 	}
@@ -89,6 +89,17 @@ func (dst *Float4) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Float4) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Float
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Float4) AssignTo(dst interface{}) error {
 	return float64AssignTo(float64(src.Float), src.Status, dst)
 }

pgtype/float4_array.go

@@ -15,7 +15,7 @@ type Float4Array struct {
 	Status     Status
 }
 
-func (dst *Float4Array) ConvertFrom(src interface{}) error {
+func (dst *Float4Array) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Float4Array:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *Float4Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Float4, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -41,7 +41,7 @@ func (dst *Float4Array) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Float4", value)
 	}
@@ -49,6 +49,17 @@ func (dst *Float4Array) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Float4Array) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Float4Array) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/float4_array_test.go

@@ -51,7 +51,7 @@ func TestFloat4ArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestFloat4ArrayConvertFrom(t *testing.T) {
+func TestFloat4ArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Float4Array
@@ -71,7 +71,7 @@ func TestFloat4ArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Float4Array
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/float4_test.go

@@ -18,7 +18,7 @@ func TestFloat4Transcode(t *testing.T) {
 	})
 }
 
-func TestFloat4ConvertFrom(t *testing.T) {
+func TestFloat4Set(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Float4
@@ -43,7 +43,7 @@ func TestFloat4ConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Float4
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/float8.go

@@ -15,7 +15,7 @@ type Float8 struct {
 	Status Status
 }
 
-func (dst *Float8) ConvertFrom(src interface{}) error {
+func (dst *Float8) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Float8:
 		*dst = value
@@ -71,7 +71,7 @@ func (dst *Float8) ConvertFrom(src interface{}) error {
 		*dst = Float8{Float: float64(num), Status: Present}
 	default:
 		if originalSrc, ok := underlyingNumberType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Float8", value)
 	}
@@ -79,6 +79,17 @@ func (dst *Float8) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Float8) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Float
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Float8) AssignTo(dst interface{}) error {
 	return float64AssignTo(src.Float, src.Status, dst)
 }

pgtype/float8_array.go

@@ -15,7 +15,7 @@ type Float8Array struct {
 	Status     Status
 }
 
-func (dst *Float8Array) ConvertFrom(src interface{}) error {
+func (dst *Float8Array) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Float8Array:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *Float8Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Float8, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -41,7 +41,7 @@ func (dst *Float8Array) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Float8", value)
 	}
@@ -49,6 +49,17 @@ func (dst *Float8Array) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Float8Array) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Float8Array) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/float8_array_test.go

@@ -51,7 +51,7 @@ func TestFloat8ArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestFloat8ArrayConvertFrom(t *testing.T) {
+func TestFloat8ArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Float8Array
@@ -71,7 +71,7 @@ func TestFloat8ArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Float8Array
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/float8_test.go

@@ -18,7 +18,7 @@ func TestFloat8Transcode(t *testing.T) {
 	})
 }
 
-func TestFloat8ConvertFrom(t *testing.T) {
+func TestFloat8Set(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Float8
@@ -43,7 +43,7 @@ func TestFloat8ConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Float8
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/inet.go

@@ -23,7 +23,7 @@ type Inet struct {
 	Status Status
 }
 
-func (dst *Inet) ConvertFrom(src interface{}) error {
+func (dst *Inet) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Inet:
 		*dst = value
@@ -43,7 +43,7 @@ func (dst *Inet) ConvertFrom(src interface{}) error {
 		*dst = Inet{IPNet: ipnet, Status: Present}
 	default:
 		if originalSrc, ok := underlyingPtrType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Inet", value)
 	}
@@ -51,6 +51,17 @@ func (dst *Inet) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Inet) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.IPNet
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Inet) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *net.IPNet:

pgtype/inet_array.go

@@ -16,7 +16,7 @@ type InetArray struct {
 	Status     Status
 }
 
-func (dst *InetArray) ConvertFrom(src interface{}) error {
+func (dst *InetArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case InetArray:
 		*dst = value
@@ -29,7 +29,7 @@ func (dst *InetArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Inet, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -48,7 +48,7 @@ func (dst *InetArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Inet, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -61,7 +61,7 @@ func (dst *InetArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Inet", value)
 	}
@@ -69,6 +69,17 @@ func (dst *InetArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *InetArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *InetArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/inet_array_test.go

@@ -52,7 +52,7 @@ func TestInetArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestInetArrayConvertFrom(t *testing.T) {
+func TestInetArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.InetArray
@@ -83,7 +83,7 @@ func TestInetArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.InetArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/inet_test.go

@@ -26,7 +26,7 @@ func TestInetTranscode(t *testing.T) {
 	}
 }
 
-func TestInetConvertFrom(t *testing.T) {
+func TestInetSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Inet
@@ -39,7 +39,7 @@ func TestInetConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Inet
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/int2.go

@@ -15,7 +15,7 @@ type Int2 struct {
 	Status Status
 }
 
-func (dst *Int2) ConvertFrom(src interface{}) error {
+func (dst *Int2) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Int2:
 		*dst = value
@@ -77,7 +77,7 @@ func (dst *Int2) ConvertFrom(src interface{}) error {
 		*dst = Int2{Int: int16(num), Status: Present}
 	default:
 		if originalSrc, ok := underlyingNumberType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Int2", value)
 	}
@@ -85,6 +85,17 @@ func (dst *Int2) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Int2) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Int
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Int2) AssignTo(dst interface{}) error {
 	return int64AssignTo(int64(src.Int), src.Status, dst)
 }

pgtype/int2_array.go

@@ -15,7 +15,7 @@ type Int2Array struct {
 	Status     Status
 }
 
-func (dst *Int2Array) ConvertFrom(src interface{}) error {
+func (dst *Int2Array) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Int2Array:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *Int2Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Int2, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -47,7 +47,7 @@ func (dst *Int2Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Int2, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -60,7 +60,7 @@ func (dst *Int2Array) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Int2", value)
 	}
@@ -68,6 +68,17 @@ func (dst *Int2Array) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Int2Array) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Int2Array) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/int2_array_test.go

@@ -51,7 +51,7 @@ func TestInt2ArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestInt2ArrayConvertFrom(t *testing.T) {
+func TestInt2ArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Int2Array
@@ -78,7 +78,7 @@ func TestInt2ArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Int2Array
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/int2_test.go

@@ -19,7 +19,7 @@ func TestInt2Transcode(t *testing.T) {
 	})
 }
 
-func TestInt2ConvertFrom(t *testing.T) {
+func TestInt2Set(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Int2
@@ -42,7 +42,7 @@ func TestInt2ConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Int2
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/int4.go

@@ -15,7 +15,7 @@ type Int4 struct {
 	Status Status
 }
 
-func (dst *Int4) ConvertFrom(src interface{}) error {
+func (dst *Int4) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Int4:
 		*dst = value
@@ -68,7 +68,7 @@ func (dst *Int4) ConvertFrom(src interface{}) error {
 		*dst = Int4{Int: int32(num), Status: Present}
 	default:
 		if originalSrc, ok := underlyingNumberType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Int8", value)
 	}
@@ -76,6 +76,17 @@ func (dst *Int4) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Int4) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Int
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Int4) AssignTo(dst interface{}) error {
 	return int64AssignTo(int64(src.Int), src.Status, dst)
 }

pgtype/int4_array.go

@@ -15,7 +15,7 @@ type Int4Array struct {
 	Status     Status
 }
 
-func (dst *Int4Array) ConvertFrom(src interface{}) error {
+func (dst *Int4Array) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Int4Array:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *Int4Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Int4, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -47,7 +47,7 @@ func (dst *Int4Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Int4, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -60,7 +60,7 @@ func (dst *Int4Array) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Int4", value)
 	}
@@ -68,6 +68,17 @@ func (dst *Int4Array) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Int4Array) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Int4Array) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/int4_array_test.go

@@ -51,7 +51,7 @@ func TestInt4ArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestInt4ArrayConvertFrom(t *testing.T) {
+func TestInt4ArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Int4Array
@@ -78,7 +78,7 @@ func TestInt4ArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Int4Array
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/int4_test.go

@@ -19,7 +19,7 @@ func TestInt4Transcode(t *testing.T) {
 	})
 }
 
-func TestInt4ConvertFrom(t *testing.T) {
+func TestInt4Set(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Int4
@@ -42,7 +42,7 @@ func TestInt4ConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Int4
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/int8.go

@@ -15,7 +15,7 @@ type Int8 struct {
 	Status Status
 }
 
-func (dst *Int8) ConvertFrom(src interface{}) error {
+func (dst *Int8) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Int8:
 		*dst = value
@@ -59,7 +59,7 @@ func (dst *Int8) ConvertFrom(src interface{}) error {
 		*dst = Int8{Int: num, Status: Present}
 	default:
 		if originalSrc, ok := underlyingNumberType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Int8", value)
 	}
@@ -67,6 +67,17 @@ func (dst *Int8) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Int8) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Int
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Int8) AssignTo(dst interface{}) error {
 	return int64AssignTo(int64(src.Int), src.Status, dst)
 }

pgtype/int8_array.go

@@ -15,7 +15,7 @@ type Int8Array struct {
 	Status     Status
 }
 
-func (dst *Int8Array) ConvertFrom(src interface{}) error {
+func (dst *Int8Array) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Int8Array:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *Int8Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Int8, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -47,7 +47,7 @@ func (dst *Int8Array) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Int8, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -60,7 +60,7 @@ func (dst *Int8Array) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Int8", value)
 	}
@@ -68,6 +68,17 @@ func (dst *Int8Array) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Int8Array) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Int8Array) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/int8_array_test.go

@@ -51,7 +51,7 @@ func TestInt8ArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestInt8ArrayConvertFrom(t *testing.T) {
+func TestInt8ArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Int8Array
@@ -78,7 +78,7 @@ func TestInt8ArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Int8Array
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/int8_test.go

@@ -19,7 +19,7 @@ func TestInt8Transcode(t *testing.T) {
 	})
 }
 
-func TestInt8ConvertFrom(t *testing.T) {
+func TestInt8Set(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Int8
@@ -42,7 +42,7 @@ func TestInt8ConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Int8
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/json.go

@@ -10,7 +10,7 @@ type Json struct {
 	Status Status
 }
 
-func (dst *Json) ConvertFrom(src interface{}) error {
+func (dst *Json) Set(src interface{}) error {
 	switch value := src.(type) {
 	case string:
 		*dst = Json{Bytes: []byte(value), Status: Present}
@@ -37,6 +37,22 @@ func (dst *Json) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Json) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		var i interface{}
+		err := json.Unmarshal(dst.Bytes, &i)
+		if err != nil {
+			return dst
+		}
+		return i
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Json) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *string:

pgtype/json_test.go

@@ -18,7 +18,7 @@ func TestJsonTranscode(t *testing.T) {
 	})
 }
 
-func TestJsonConvertFrom(t *testing.T) {
+func TestJsonSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Json
@@ -33,7 +33,7 @@ func TestJsonConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var d pgtype.Json
-		err := d.ConvertFrom(tt.source)
+		err := d.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/jsonb.go

@@ -7,8 +7,12 @@ import (
 
 type Jsonb Json
 
-func (dst *Jsonb) ConvertFrom(src interface{}) error {
+func (dst *Jsonb) Set(src interface{}) error {
-	return (*Json)(dst).ConvertFrom(src)
+	return (*Json)(dst).Set(src)
+}
+
+func (dst *Jsonb) Get() interface{} {
+	return (*Json)(dst).Get()
 }
 
 func (src *Jsonb) AssignTo(dst interface{}) error {

pgtype/jsonb_test.go

@@ -18,7 +18,7 @@ func TestJsonbTranscode(t *testing.T) {
 	})
 }
 
-func TestJsonbConvertFrom(t *testing.T) {
+func TestJsonbSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Jsonb
@@ -33,7 +33,7 @@ func TestJsonbConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var d pgtype.Jsonb
-		err := d.ConvertFrom(tt.source)
+		err := d.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/name.go

@@ -19,8 +19,12 @@ import (
 // bytes applies, rather than the default 63.
 type Name Text
 
-func (dst *Name) ConvertFrom(src interface{}) error {
+func (dst *Name) Set(src interface{}) error {
-	return (*Text)(dst).ConvertFrom(src)
+	return (*Text)(dst).Set(src)
+}
+
+func (dst *Name) Get() interface{} {
+	return (*Text)(dst).Get()
 }
 
 func (src *Name) AssignTo(dst interface{}) error {

pgtype/name_test.go

@@ -15,7 +15,7 @@ func TestNameTranscode(t *testing.T) {
 	})
 }
 
-func TestNameConvertFrom(t *testing.T) {
+func TestNameSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Name
@@ -27,7 +27,7 @@ func TestNameConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var d pgtype.Name
-		err := d.ConvertFrom(tt.source)
+		err := d.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/oid.go

@@ -11,11 +11,15 @@ import (
 // found in src/include/postgres_ext.h in the PostgreSQL sources.
 type Oid pguint32
 
-// ConvertFrom converts from src to dst. Note that as Oid is not a general
+// Set converts from src to dst. Note that as Oid is not a general
-// number type ConvertFrom does not do automatic type conversion as other number
+// number type Set does not do automatic type conversion as other number
 // types do.
-func (dst *Oid) ConvertFrom(src interface{}) error {
+func (dst *Oid) Set(src interface{}) error {
-	return (*pguint32)(dst).ConvertFrom(src)
+	return (*pguint32)(dst).Set(src)
+}
+
+func (dst *Oid) Get() interface{} {
+	return (*pguint32)(dst).Get()
 }
 
 // AssignTo assigns from src to dst. Note that as Oid is not a general number

pgtype/oid_test.go

@@ -14,7 +14,7 @@ func TestOidTranscode(t *testing.T) {
 	})
 }
 
-func TestOidConvertFrom(t *testing.T) {
+func TestOidSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Oid
@@ -24,7 +24,7 @@ func TestOidConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Oid
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/pgtype.go

@@ -66,13 +66,16 @@ const (
 	NegativeInfinity InfinityModifier = -Infinity
 )
 
-type Value interface{}
+type Value interface {
+	// Set converts and assigns src to itself.
+	Set(src interface{}) error
 
-type ConverterFrom interface {
+	// Get returns the simplest representation of Value. If the Value is Null or
-	ConvertFrom(src interface{}) error
+	// Undefined that is the return value. If no simpler representation is
-}
+	// possible, then Get() returns Value.
+	Get() interface{}
 
-type AssignerTo interface {
+	// AssignTo converts and assigns the Value to dst.
 	AssignTo(dst interface{}) error
 }
 

pgtype/pguint32.go

@@ -16,10 +16,10 @@ type pguint32 struct {
 	Status Status
 }
 
-// ConvertFrom converts from src to dst. Note that as pguint32 is not a general
+// Set converts from src to dst. Note that as pguint32 is not a general
-// number type ConvertFrom does not do automatic type conversion as other number
+// number type Set does not do automatic type conversion as other number
 // types do.
-func (dst *pguint32) ConvertFrom(src interface{}) error {
+func (dst *pguint32) Set(src interface{}) error {
 	switch value := src.(type) {
 	case uint32:
 		*dst = pguint32{Uint: value, Status: Present}
@@ -30,6 +30,17 @@ func (dst *pguint32) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *pguint32) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Uint
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 // AssignTo assigns from src to dst. Note that as pguint32 is not a general number
 // type AssignTo does not do automatic type conversion as other number types do.
 func (src *pguint32) AssignTo(dst interface{}) error {

pgtype/qchar.go

@@ -23,7 +23,7 @@ type QChar struct {
 	Status Status
 }
 
-func (dst *QChar) ConvertFrom(src interface{}) error {
+func (dst *QChar) Set(src interface{}) error {
 	switch value := src.(type) {
 	case QChar:
 		*dst = value
@@ -94,7 +94,7 @@ func (dst *QChar) ConvertFrom(src interface{}) error {
 		*dst = QChar{Int: int8(num), Status: Present}
 	default:
 		if originalSrc, ok := underlyingNumberType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to QChar", value)
 	}
@@ -102,6 +102,17 @@ func (dst *QChar) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *QChar) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.Int
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *QChar) AssignTo(dst interface{}) error {
 	return int64AssignTo(int64(src.Int), src.Status, dst)
 }

pgtype/qchar_test.go

@@ -19,7 +19,7 @@ func TestQCharTranscode(t *testing.T) {
 	})
 }
 
-func TestQCharConvertFrom(t *testing.T) {
+func TestQCharSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.QChar
@@ -42,7 +42,7 @@ func TestQCharConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.QChar
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/text.go

@@ -11,7 +11,7 @@ type Text struct {
 	Status Status
 }
 
-func (dst *Text) ConvertFrom(src interface{}) error {
+func (dst *Text) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Text:
 		*dst = value
@@ -25,7 +25,7 @@ func (dst *Text) ConvertFrom(src interface{}) error {
 		}
 	default:
 		if originalSrc, ok := underlyingStringType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Text", value)
 	}
@@ -33,6 +33,17 @@ func (dst *Text) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Text) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst.String
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Text) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *string:

pgtype/text_array.go

@@ -15,7 +15,7 @@ type TextArray struct {
 	Status     Status
 }
 
-func (dst *TextArray) ConvertFrom(src interface{}) error {
+func (dst *TextArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case TextArray:
 		*dst = value
@@ -28,7 +28,7 @@ func (dst *TextArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Text, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -41,7 +41,7 @@ func (dst *TextArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Text", value)
 	}
@@ -49,6 +49,17 @@ func (dst *TextArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *TextArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *TextArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/text_array_test.go

@@ -51,7 +51,7 @@ func TestTextArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestTextArrayConvertFrom(t *testing.T) {
+func TestTextArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.TextArray
@@ -71,7 +71,7 @@ func TestTextArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.TextArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/text_test.go

@@ -17,7 +17,7 @@ func TestTextTranscode(t *testing.T) {
 	}
 }
 
-func TestTextConvertFrom(t *testing.T) {
+func TestTextSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Text
@@ -30,7 +30,7 @@ func TestTextConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var d pgtype.Text
-		err := d.ConvertFrom(tt.source)
+		err := d.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/tid.go

@@ -27,6 +27,25 @@ type Tid struct {
 	Status       Status
 }
 
+func (dst *Tid) Set(src interface{}) error {
+	return fmt.Errorf("cannot convert %v to Tid", src)
+}
+
+func (dst *Tid) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
+func (src *Tid) AssignTo(dst interface{}) error {
+	return fmt.Errorf("cannot assign %v to %T", src, dst)
+}
+
 func (dst *Tid) DecodeText(src []byte) error {
 	if src == nil {
 		*dst = Tid{Status: Null}

pgtype/timestamp.go

@@ -23,9 +23,9 @@ type Timestamp struct {
 	InfinityModifier
 }
 
-// ConvertFrom converts src into a Timestamp and stores in dst. If src is a
+// Set converts src into a Timestamp and stores in dst. If src is a
 // time.Time in a non-UTC time zone, the time zone is discarded.
-func (dst *Timestamp) ConvertFrom(src interface{}) error {
+func (dst *Timestamp) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Timestamp:
 		*dst = value
@@ -33,7 +33,7 @@ func (dst *Timestamp) ConvertFrom(src interface{}) error {
 		*dst = Timestamp{Time: time.Date(value.Year(), value.Month(), value.Day(), value.Hour(), value.Minute(), value.Second(), value.Nanosecond(), time.UTC), Status: Present}
 	default:
 		if originalSrc, ok := underlyingTimeType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Timestamp", value)
 	}
@@ -41,6 +41,20 @@ func (dst *Timestamp) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Timestamp) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		if dst.InfinityModifier != None {
+			return dst.InfinityModifier
+		}
+		return dst.Time
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Timestamp) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *time.Time:

pgtype/timestamp_array.go

@@ -16,7 +16,7 @@ type TimestampArray struct {
 	Status     Status
 }
 
-func (dst *TimestampArray) ConvertFrom(src interface{}) error {
+func (dst *TimestampArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case TimestampArray:
 		*dst = value
@@ -29,7 +29,7 @@ func (dst *TimestampArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Timestamp, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -42,7 +42,7 @@ func (dst *TimestampArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Timestamp", value)
 	}
@@ -50,6 +50,17 @@ func (dst *TimestampArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *TimestampArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *TimestampArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/timestamp_array_test.go

@@ -68,7 +68,7 @@ func TestTimestampArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestTimestampArrayConvertFrom(t *testing.T) {
+func TestTimestampArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.TimestampArray
@@ -88,7 +88,7 @@ func TestTimestampArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.TimestampArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/timestamp_test.go

@@ -31,7 +31,7 @@ func TestTimestampTranscode(t *testing.T) {
 	})
 }
 
-func TestTimestampConvertFrom(t *testing.T) {
+func TestTimestampSet(t *testing.T) {
 	type _time time.Time
 
 	successfulTests := []struct {
@@ -51,7 +51,7 @@ func TestTimestampConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Timestamp
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/timestamptz.go

@@ -26,7 +26,7 @@ type Timestamptz struct {
 	InfinityModifier
 }
 
-func (dst *Timestamptz) ConvertFrom(src interface{}) error {
+func (dst *Timestamptz) Set(src interface{}) error {
 	switch value := src.(type) {
 	case Timestamptz:
 		*dst = value
@@ -34,7 +34,7 @@ func (dst *Timestamptz) ConvertFrom(src interface{}) error {
 		*dst = Timestamptz{Time: value, Status: Present}
 	default:
 		if originalSrc, ok := underlyingTimeType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Timestamptz", value)
 	}
@@ -42,6 +42,20 @@ func (dst *Timestamptz) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *Timestamptz) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		if dst.InfinityModifier != None {
+			return dst.InfinityModifier
+		}
+		return dst.Time
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *Timestamptz) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	case *time.Time:

pgtype/timestamptz_array.go

@@ -16,7 +16,7 @@ type TimestamptzArray struct {
 	Status     Status
 }
 
-func (dst *TimestamptzArray) ConvertFrom(src interface{}) error {
+func (dst *TimestamptzArray) Set(src interface{}) error {
 	switch value := src.(type) {
 	case TimestamptzArray:
 		*dst = value
@@ -29,7 +29,7 @@ func (dst *TimestamptzArray) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]Timestamptz, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -42,7 +42,7 @@ func (dst *TimestamptzArray) ConvertFrom(src interface{}) error {
 
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to Timestamptz", value)
 	}
@@ -50,6 +50,17 @@ func (dst *TimestamptzArray) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *TimestamptzArray) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *TimestamptzArray) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 

pgtype/timestamptz_array_test.go

@@ -68,7 +68,7 @@ func TestTimestamptzArrayTranscode(t *testing.T) {
 	})
 }
 
-func TestTimestamptzArrayConvertFrom(t *testing.T) {
+func TestTimestamptzArraySet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.TimestamptzArray
@@ -88,7 +88,7 @@ func TestTimestamptzArrayConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.TimestamptzArray
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/timestamptz_test.go

@@ -31,7 +31,7 @@ func TestTimestamptzTranscode(t *testing.T) {
 	})
 }
 
-func TestTimestamptzConvertFrom(t *testing.T) {
+func TestTimestamptzSet(t *testing.T) {
 	type _time time.Time
 
 	successfulTests := []struct {
@@ -50,7 +50,7 @@ func TestTimestamptzConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Timestamptz
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

pgtype/typed_array.go.erb

@@ -14,7 +14,7 @@ type <%= pgtype_array_type %> struct {
 	Status     Status
 }
 
-func (dst *<%= pgtype_array_type %>) ConvertFrom(src interface{}) error {
+func (dst *<%= pgtype_array_type %>) Set(src interface{}) error {
 	switch value := src.(type) {
 	case <%= pgtype_array_type %>:
 		*dst = value
@@ -27,7 +27,7 @@ func (dst *<%= pgtype_array_type %>) ConvertFrom(src interface{}) error {
 		} else {
 			elements := make([]<%= pgtype_element_type %>, len(value))
 			for i := range value {
-				if err := elements[i].ConvertFrom(value[i]); err != nil {
+				if err := elements[i].Set(value[i]); err != nil {
 					return err
 				}
 			}
@@ -40,7 +40,7 @@ func (dst *<%= pgtype_array_type %>) ConvertFrom(src interface{}) error {
 	<% end %>
 	default:
 		if originalSrc, ok := underlyingSliceType(src); ok {
-			return dst.ConvertFrom(originalSrc)
+			return dst.Set(originalSrc)
 		}
 		return fmt.Errorf("cannot convert %v to <%= pgtype_element_type %>", value)
 	}
@@ -48,6 +48,17 @@ func (dst *<%= pgtype_array_type %>) ConvertFrom(src interface{}) error {
 	return nil
 }
 
+func (dst *<%= pgtype_array_type %>) Get() interface{} {
+	switch dst.Status {
+	case Present:
+		return dst
+	case Null:
+		return nil
+	default:
+		return dst.Status
+	}
+}
+
 func (src *<%= pgtype_array_type %>) AssignTo(dst interface{}) error {
 	switch v := dst.(type) {
 	<% go_array_types.split(",").each do |t| %>

pgtype/varchar_array.go

@@ -6,8 +6,12 @@ import (
 
 type VarcharArray TextArray
 
-func (dst *VarcharArray) ConvertFrom(src interface{}) error {
+func (dst *VarcharArray) Set(src interface{}) error {
-	return (*TextArray)(dst).ConvertFrom(src)
+	return (*TextArray)(dst).Set(src)
+}
+
+func (dst *VarcharArray) Get() interface{} {
+	return (*TextArray)(dst).Get()
 }
 
 func (src *VarcharArray) AssignTo(dst interface{}) error {

pgtype/xid.go

@@ -20,11 +20,15 @@ import (
 // in the PostgreSQL sources.
 type Xid pguint32
 
-// ConvertFrom converts from src to dst. Note that as Xid is not a general
+// Set converts from src to dst. Note that as Xid is not a general
-// number type ConvertFrom does not do automatic type conversion as other number
+// number type Set does not do automatic type conversion as other number
 // types do.
-func (dst *Xid) ConvertFrom(src interface{}) error {
+func (dst *Xid) Set(src interface{}) error {
-	return (*pguint32)(dst).ConvertFrom(src)
+	return (*pguint32)(dst).Set(src)
+}
+
+func (dst *Xid) Get() interface{} {
+	return (*pguint32)(dst).Get()
 }
 
 // AssignTo assigns from src to dst. Note that as Xid is not a general number

pgtype/xid_test.go

@@ -14,7 +14,7 @@ func TestXidTranscode(t *testing.T) {
 	})
 }
 
-func TestXidConvertFrom(t *testing.T) {
+func TestXidSet(t *testing.T) {
 	successfulTests := []struct {
 		source interface{}
 		result pgtype.Xid
@@ -24,7 +24,7 @@ func TestXidConvertFrom(t *testing.T) {
 
 	for i, tt := range successfulTests {
 		var r pgtype.Xid
-		err := r.ConvertFrom(tt.source)
+		err := r.Set(tt.source)
 		if err != nil {
 			t.Errorf("%d: %v", i, err)
 		}

query.go

@@ -288,12 +288,8 @@ func (rows *Rows) Scan(dest ...interface{}) (err error) {
 					vr.Fatal(fmt.Errorf("unknown format code: %v", vr.Type().FormatCode))
 				}
 
-				if assignerTo, ok := pgVal.(pgtype.AssignerTo); ok {
+				if err := pgVal.AssignTo(d); err != nil {
-					if err := assignerTo.AssignTo(d); err != nil {
+					vr.Fatal(err)
-						vr.Fatal(err)
-					}
-				} else {
-					vr.Fatal(fmt.Errorf("cannot assign %T", pgVal))
 				}
 			} else {
 				if err := Decode(vr, d); err != nil {

values.go

@@ -773,13 +773,9 @@ func Encode(wbuf *WriteBuf, oid Oid, arg interface{}) error {
 	}
 
 	if value, ok := wbuf.conn.oidPgtypeValues[oid]; ok {
-		if converterFrom, ok := value.(pgtype.ConverterFrom); ok {
+		err := value.Set(arg)
-			err := converterFrom.ConvertFrom(arg)
+		if err != nil {
-			if err != nil {
+			return err
-				return err
-			}
-		} else {
-			return SerializationError(fmt.Sprintf("Cannot encode %T into oid %v - %T must implement Encoder or be converted to a string", arg, oid, arg))
 		}
 
 		buf := &bytes.Buffer{}
@@ -1275,7 +1271,7 @@ func encodeTime(w *WriteBuf, oid Oid, value time.Time) error {
 	switch oid {
 	case DateOid:
 		var d pgtype.Date
-		err := d.ConvertFrom(value)
+		err := d.Set(value)
 		if err != nil {
 			return err
 		}
@@ -1295,7 +1291,7 @@ func encodeTime(w *WriteBuf, oid Oid, value time.Time) error {
 
 	case TimestampTzOid, TimestampOid:
 		var t pgtype.Timestamptz
-		err := t.ConvertFrom(value)
+		err := t.Set(value)
 		if err != nil {
 			return err
 		}