Struct fields numeric labels

Makefile

@@ -5,7 +5,7 @@
 # normal `go install`.
 
 # generated integration test files
-GGEN = ./_generated/generated.go ./_generated/generated_test.go
+GGEN = ./_generated/generated.go ./_generated/generated_test.go ./_generated/issue94_gen.go ./_generated/issue94_gen_test.go
 # generated unit test files
 MGEN = ./msgp/defgen_test.go
 

README.md

@@ -42,6 +42,16 @@ type Person struct {
 	unexported bool             // this field is also ignored
 }
 ```
+If you need to have numeric labels for a struct fields, you could set it as following:
+```go
+type Person struct {
+	Name       string `msg:"0x01,int"`
+	Address    string `msg:"0b10,int"`
+	Email      string `msg:"03,int"`
+	Age        int    `msg:"4,int"`
+}
+```
+> Note that field labels with `uint` value will be serialized as `msgp.fixint` in case when label value is <= (1<<7)-1
 
 By default, the code generator will satisfy `msgp.Sizer`, `msgp.Encodable`, `msgp.Decodable`, 
 `msgp.Marshaler`, and `msgp.Unmarshaler`. Carefully-designed applications can use these methods to do

_generated/def.go

@@ -41,9 +41,9 @@ type TestType struct {
 	F   *float64          `msg:"float"`
 	Els map[string]string `msg:"elements"`
 	Obj struct {          // test anonymous struct
-		ValueA string `msg:"value_a"`
-		ValueB []byte `msg:"value_b"`
-	} `msg:"object"`
+		    ValueA string `msg:"value_a"`
+		    ValueB []byte `msg:"value_b"`
+	    } `msg:"object"`
 	Child    *TestType   `msg:"child"`
 	Time     time.Time   `msg:"time"`
 	Any      interface{} `msg:"any"`
@@ -53,6 +53,28 @@ type TestType struct {
 	Slice2   []string
 }
 
+type TestNumericLabels struct {
+	One string `msg:"0x01,int"`
+	Two string `msg:"0xffffffffffffffff,uint"`
+}
+
+type TestOnlyIntLabels struct {
+	A string `msg:"0xfa,int"`
+	B string `msg:"0xfb,int"`
+	C string `msg:"0xfc,int"`
+}
+
+type TestIntLiterals struct {
+	A string `msg:"0x01,int"`
+	B string `msg:"0b10,int"`
+	C string `msg:"03,int"`
+	D string `msg:"4,int"`
+}
+
+type SingleFieldNumeric struct {
+	Message string `msg:"0x00,uint"`
+}
+
 //msgp:tuple Object
 type Object struct {
 	ObjectNo string   `msg:"objno"`

gen/decode.go

@@ -7,33 +7,24 @@ import (
 
 func decode(w io.Writer) *decodeGen {
 	return &decodeGen{
-		p:        printer{w: w},
-		hasfield: false,
+		p: printer{w: w},
 	}
 }
 
 type decodeGen struct {
 	passes
-	p        printer
-	hasfield bool
+	fields
+	p printer
 }
 
 func (d *decodeGen) Method() Method { return Decode }
 
-func (d *decodeGen) needsField() {
-	if d.hasfield {
-		return
-	}
-	d.p.print("\nvar field []byte; _ = field")
-	d.hasfield = true
-}
-
 func (d *decodeGen) Execute(p Elem) error {
 	p = d.applyall(p)
 	if p == nil {
 		return nil
 	}
-	d.hasfield = false
+	d.fields.drop()
 	if !d.p.ok() {
 		return d.p.err
 	}
@@ -63,14 +54,32 @@ func (d *decodeGen) gStruct(s *Struct) {
 	return
 }
 
-func (d *decodeGen) assignAndCheck(name string, typ string) {
+func (d *decodeGen) assignAndCheck(name string, base string) {
 	if !d.p.ok() {
 		return
 	}
-	d.p.printf("\n%s, err = dc.Read%s()", name, typ)
+	if base == mapKey {
+		d.p.printf("\n%s, err = dc.ReadMapKeyPtr()", name)
+	} else {
+		d.p.printf("\n%s, err = dc.Read%s()", name, base)
+	}
+
 	d.p.print(errcheck)
 }
 
+func (u *decodeGen) nextTypeAndCheck(name string) {
+	if !u.p.ok() {
+		return
+	}
+	u.p.printf("\n%s, err = dc.NextType()", name)
+	u.p.print(errcheck)
+}
+
+func (u *decodeGen) skipAndCheck() {
+	u.p.print("\nerr = dc.Skip()")
+	u.p.print(errcheck)
+}
+
 func (d *decodeGen) structAsTuple(s *Struct) {
 	nfields := len(s.Fields)
 
@@ -87,25 +96,7 @@ func (d *decodeGen) structAsTuple(s *Struct) {
 }
 
 func (d *decodeGen) structAsMap(s *Struct) {
-	d.needsField()
-	sz := randIdent()
-	d.p.declare(sz, u32)
-	d.assignAndCheck(sz, mapHeader)
-
-	d.p.printf("\nfor %s > 0 {\n%s--", sz, sz)
-	d.assignAndCheck("field", mapKey)
-	d.p.print("\nswitch msgp.UnsafeString(field) {")
-	for i := range s.Fields {
-		d.p.printf("\ncase \"%s\":", s.Fields[i].FieldTag)
-		next(d, s.Fields[i].FieldElem)
-		if !d.p.ok() {
-			return
-		}
-	}
-	d.p.print("\ndefault:\nerr = dc.Skip()")
-	d.p.print(errcheck)
-	d.p.closeblock() // close switch
-	d.p.closeblock() // close for loop
+	genStructFieldsParser(d, d.p, s.Fields)
 }
 
 func (d *decodeGen) gBase(b *BaseElem) {

gen/elem.go

@@ -396,9 +396,9 @@ func (s *Struct) Complexity() int {
 }
 
 type StructField struct {
-	FieldTag  string // the string inside the `msg:""` tag
-	FieldName string // the name of the struct field
-	FieldElem Elem   // the field type
+	FieldTag  interface{} // the label of the struct field in msgpack
+	FieldName string      // the name of the struct field
+	FieldElem Elem        // the field type
 }
 
 // BaseElem is an element that

gen/encode.go

@@ -2,8 +2,9 @@ package gen
 
 import (
 	"fmt"
-	"github.com/tinylib/msgp/msgp"
 	"io"
+
+	"github.com/tinylib/msgp/msgp"
 )
 
 func encode(w io.Writer) *encodeGen {
@@ -101,19 +102,7 @@ func (e *encodeGen) appendraw(bts []byte) {
 }
 
 func (e *encodeGen) structmap(s *Struct) {
-	nfields := len(s.Fields)
-	data := msgp.AppendMapHeader(nil, uint32(nfields))
-	e.p.printf("\n// map header, size %d", nfields)
-	e.Fuse(data)
-	for i := range s.Fields {
-		if !e.p.ok() {
-			return
-		}
-		data = msgp.AppendString(nil, s.Fields[i].FieldTag)
-		e.p.printf("\n// write %q", s.Fields[i].FieldTag)
-		e.Fuse(data)
-		next(e, s.Fields[i].FieldElem)
-	}
+	genStructFieldsSerializer(e, e.p, s.Fields)
 }
 
 func (e *encodeGen) gMap(m *Map) {

gen/marshal.go

@@ -2,8 +2,9 @@ package gen
 
 import (
 	"fmt"
-	"github.com/tinylib/msgp/msgp"
 	"io"
+
+	"github.com/tinylib/msgp/msgp"
 )
 
 func marshal(w io.Writer) *marshalGen {
@@ -96,21 +97,7 @@ func (m *marshalGen) tuple(s *Struct) {
 }
 
 func (m *marshalGen) mapstruct(s *Struct) {
-	data := make([]byte, 0, 64)
-	data = msgp.AppendMapHeader(data, uint32(len(s.Fields)))
-	m.p.printf("\n// map header, size %d", len(s.Fields))
-	m.Fuse(data)
-	for i := range s.Fields {
-		if !m.p.ok() {
-			return
-		}
-		data = msgp.AppendString(nil, s.Fields[i].FieldTag)
-
-		m.p.printf("\n// string %q", s.Fields[i].FieldTag)
-		m.Fuse(data)
-
-		next(m, s.Fields[i].FieldElem)
-	}
+	genStructFieldsSerializer(m, m.p, s.Fields)
 }
 
 // append raw data

gen/size.go

@@ -2,9 +2,10 @@ package gen
 
 import (
 	"fmt"
-	"github.com/tinylib/msgp/msgp"
 	"io"
 	"strconv"
+
+	"github.com/tinylib/msgp/msgp"
 )
 
 type sizeState uint8
@@ -107,7 +108,7 @@ func (s *sizeGen) gStruct(st *Struct) {
 		s.addConstant(strconv.Itoa(len(data)))
 		for i := range st.Fields {
 			data = data[:0]
-			data = msgp.AppendString(data, st.Fields[i].FieldTag)
+			data, s.p.err = msgp.AppendIntf(data, st.Fields[i].FieldTag)
 			s.addConstant(strconv.Itoa(len(data)))
 			next(s, st.Fields[i].FieldElem)
 		}
@@ -238,8 +239,12 @@ func fixedsizeExpr(e Elem) (string, bool) {
 		mhdr := msgp.AppendMapHeader(nil, uint32(len(e.Fields)))
 		hdrlen += len(mhdr)
 		var strbody []byte
+		var err error
 		for _, f := range e.Fields {
-			strbody = msgp.AppendString(strbody[:0], f.FieldTag)
+			strbody, err = msgp.AppendIntf(strbody[:0], f.FieldTag)
+			if err != nil {
+				return "", false
+			}
 			hdrlen += len(strbody)
 		}
 		return fmt.Sprintf("%d + %s", hdrlen, str), true