Refactor Atom and Value code out of walk.go and into separate files

3 files changed, 185 insertions, 174 deletions

diff --git a/walk/atom.go b/walk/atom.go
new file mode 100644
index 0000000..13ad2ff
--- /dev/null
+++ b/walk/atom.go
@@ -0,0 +1,95 @@
+package walk
+
+import (
+	"math"
+	"fmt"
+)
+
+type AtomType int64
+const (
+	AtomNull AtomType = iota
+	AtomBool
+	AtomNumber
+	AtomTerminal
+	AtomStringTerminal
+	AtomStringRune
+)
+type Atom struct {
+	Typ AtomType
+	data uint64
+}
+func NewAtomNull() Atom {
+	return Atom {
+		Typ: AtomNull,
+		data: 0,
+	}
+}
+func NewAtomBool(v bool) Atom {
+	if v {
+		return Atom {
+			Typ: AtomBool,
+			data: 1,
+		}
+	} else {
+		return Atom {
+			Typ: AtomBool,
+			data: 0,
+		}
+	}
+}
+func NewAtomNumber(v float64) Atom {
+	return Atom {
+		Typ: AtomNumber,
+		data: math.Float64bits(v),
+	}
+}
+func NewAtomTerminal(v ValueTerminal) Atom {
+	return Atom {
+		Typ: AtomTerminal,
+		data: uint64(v),
+	}
+}
+func NewAtomStringTerminal() Atom {
+	return Atom {
+		Typ: AtomStringTerminal,
+		data: 0,
+	}
+}
+func NewAtomStringRune(v rune) Atom {
+	return Atom {
+		Typ: AtomStringRune,
+		data: uint64(v),
+	}
+}
+func (v Atom) String() string {
+	switch v.Typ {
+		case AtomNull:
+			return "null"
+		case AtomBool:
+			if v.data == 0 {
+				return "false"
+			}
+			return "true"
+		case AtomNumber:
+			return fmt.Sprintf("%v", math.Float64frombits(v.data))
+		case AtomTerminal:
+			switch ValueTerminal(v.data) {
+				case MapBegin:
+					return "{"
+				case MapEnd:
+					return "}"
+				case ArrayBegin:
+					return "["
+				case ArrayEnd:
+					return "]"
+				default:
+					panic("Invalid terminal atom")
+			}
+		case AtomStringTerminal:
+			return "\""
+		case AtomStringRune:
+			return string(rune(v.data))
+		default:
+			panic("Invalid atom type")
+	}
+}
diff --git a/walk/value.go b/walk/value.go
new file mode 100644
index 0000000..2e2c3c9
--- /dev/null
+++ b/walk/value.go
@@ -0,0 +1,78 @@
+package walk
+
+import (
+	"fmt"
+)
+
+type ValueTerminal int
+const (
+	ArrayBegin ValueTerminal = iota
+	ArrayEnd
+	MapBegin
+	MapEnd
+)
+func (value ValueTerminal) Atomise(in []Atom) []Atom {
+	return append(in, NewAtomTerminal(value))
+}
+func (value ValueTerminal) String() string {
+	switch value {
+		case ArrayBegin:
+			return "["
+		case ArrayEnd:
+			return "]"
+		case MapBegin:
+			return "{"
+		case MapEnd:
+			return "}"
+		default:
+			panic("Unknown TerminalValue")
+	}
+}
+
+type ValueNull struct {}
+func (value ValueNull) Atomise(in []Atom) []Atom {
+	return append(in, NewAtomNull())
+}
+func (value ValueNull) String() string {
+	return "null"
+}
+
+type ValueBool bool
+func (value ValueBool) Atomise(in []Atom) []Atom {
+	return append(in, NewAtomBool(bool(value)))
+}
+func (value ValueBool) String() string {
+	if value {
+		return "true"
+	} else {
+		return "false"
+	}
+}
+
+type ValueNumber float64
+func (value ValueNumber) Atomise(in []Atom) []Atom {
+	return append(in, NewAtomNumber(float64(value)))
+}
+func (value ValueNumber) String() string {
+	v := float64(value)
+	return fmt.Sprintf("%f", v)
+}
+
+type ValueString string
+func (value ValueString) Atomise(in []Atom) []Atom {
+	in = append(in, NewAtomStringTerminal())
+	for _, char := range value {
+		in = append(in, NewAtomStringRune(char))
+	}
+	in = append(in, NewAtomStringTerminal())
+	return in
+}
+func (value ValueString) String() string {
+	return fmt.Sprintf("\"%s\"", string(value))
+}
+
+type Value interface {
+	// Append this values atoms to the input
+	Atomise(in []Atom) []Atom
+	String() string
+}
diff --git a/walk/walk.go b/walk/walk.go
index 493bc46..20eac38 100644
--- a/walk/walk.go
+++ b/walk/walk.go
@@ -15,8 +15,8 @@ func stringPathSegment(segment PathSegment) string {
 	return fmt.Sprintf("%v", segment)
 }
 type Path []PathSegment
-func (path Path) ToWalkValues() []WalkValue {
-	var values []WalkValue
+func (path Path) ToWalkValues() []Value {
+	var values []Value
 	for _, segment := range path {
 		switch s := segment.(type) {
 			case int:
@@ -30,7 +30,7 @@ func (path Path) ToWalkValues() []WalkValue {
 	return values
 }
 
-func PathFromWalkValues(values []WalkValue) Path {
+func PathFromWalkValues(values []Value) Path {
 	var segments []PathSegment
 	for _, value := range values {
 		switch v := value.(type) {
@@ -45,168 +45,6 @@ func PathFromWalkValues(values []WalkValue) Path {
 	return segments
 }
 
-type TerminalValue int
-const (
-	ArrayBegin TerminalValue = iota
-	ArrayEnd
-	MapBegin
-	MapEnd
-)
-func (value TerminalValue) Atomise(in []Atom) []Atom {
-	return append(in, NewAtomTerminal(value))
-}
-func (value TerminalValue) String() string {
-	switch value {
-		case ArrayBegin:
-			return "["
-		case ArrayEnd:
-			return "]"
-		case MapBegin:
-			return "{"
-		case MapEnd:
-			return "}"
-		default:
-			panic("Unknown TerminalValue")
-	}
-}
-
-type ValueNull struct {}
-func (value ValueNull) Atomise(in []Atom) []Atom {
-	return append(in, NewAtomNull())
-}
-func (value ValueNull) String() string {
-	return "null"
-}
-
-type ValueBool bool
-func (value ValueBool) Atomise(in []Atom) []Atom {
-	return append(in, NewAtomBool(bool(value)))
-}
-func (value ValueBool) String() string {
-	if value {
-		return "true"
-	} else {
-		return "false"
-	}
-}
-
-type ValueNumber float64
-func (value ValueNumber) Atomise(in []Atom) []Atom {
-	return append(in, NewAtomNumber(float64(value)))
-}
-func (value ValueNumber) String() string {
-	v := float64(value)
-	return fmt.Sprintf("%f", v)
-}
-
-type ValueString string
-func (value ValueString) Atomise(in []Atom) []Atom {
-	in = append(in, NewAtomStringTerminal())
-	for _, char := range value {
-		in = append(in, NewAtomStringRune(char))
-	}
-	in = append(in, NewAtomStringTerminal())
-	return in
-}
-func (value ValueString) String() string {
-	return fmt.Sprintf("\"%s\"", string(value))
-}
-
-type AtomType int64
-const (
-	AtomNull AtomType = iota
-	AtomBool
-	AtomNumber
-	AtomTerminal
-	AtomStringTerminal
-	AtomStringRune
-)
-type Atom struct {
-	Typ AtomType
-	data uint64
-}
-func NewAtomNull() Atom {
-	return Atom {
-		Typ: AtomNull,
-		data: 0,
-	}
-}
-func NewAtomBool(v bool) Atom {
-	if v {
-		return Atom {
-			Typ: AtomBool,
-			data: 1,
-		}
-	} else {
-		return Atom {
-			Typ: AtomBool,
-			data: 0,
-		}
-	}
-}
-func NewAtomNumber(v float64) Atom {
-	return Atom {
-		Typ: AtomNumber,
-		data: math.Float64bits(v),
-	}
-}
-func NewAtomTerminal(v TerminalValue) Atom {
-	return Atom {
-		Typ: AtomTerminal,
-		data: uint64(v),
-	}
-}
-func NewAtomStringTerminal() Atom {
-	return Atom {
-		Typ: AtomStringTerminal,
-		data: 0,
-	}
-}
-func NewAtomStringRune(v rune) Atom {
-	return Atom {
-		Typ: AtomStringRune,
-		data: uint64(v),
-	}
-}
-func (v Atom) String() string {
-	switch v.Typ {
-		case AtomNull:
-			return "null"
-		case AtomBool:
-			if v.data == 0 {
-				return "false"
-			}
-			return "true"
-		case AtomNumber:
-			return fmt.Sprintf("%v", math.Float64frombits(v.data))
-		case AtomTerminal:
-			switch TerminalValue(v.data) {
-				case MapBegin:
-					return "{"
-				case MapEnd:
-					return "}"
-				case ArrayBegin:
-					return "["
-				case ArrayEnd:
-					return "]"
-				default:
-					panic("Invalid terminal atom")
-			}
-		case AtomStringTerminal:
-			return "\""
-		case AtomStringRune:
-			return string(rune(v.data))
-		default:
-			panic("Invalid atom type")
-	}
-}
-
-type WalkValue interface {
-	// Append this values atoms to the input
-	Atomise(in []Atom) []Atom
-	String() string
-}
-
 type WalkItem struct {
 	Value []Atom
 	Path []Atom
@@ -527,7 +365,7 @@ func (out *JSONOut) atomOut(key string, atom Atom) {
 					fmt.Fprint(out.writer, "\"")
 					out.structure = append(out.structure, JSONOutString)
 				case AtomTerminal:
-					switch TerminalValue(atom.data) {
+					switch ValueTerminal(atom.data) {
 						case MapBegin:
 							out.indent(0)
 							if state == JSONOutMap {
@@ -565,12 +403,12 @@ func (out *JSONOut) atomOut(key string, atom Atom) {
 		case JSONOutValueEnd:
 			out.structure = out.structure[:len(out.structure) - 1]
 			underState := out.structure[len(out.structure) - 1]
-			if underState == JSONOutMap && atom.Typ == AtomTerminal && TerminalValue(atom.data) == MapEnd {
+			if underState == JSONOutMap && atom.Typ == AtomTerminal && ValueTerminal(atom.data) == MapEnd {
 				fmt.Fprint(out.writer, "\n")
 				out.indent(-1)
 				fmt.Fprint(out.writer, "}")
 				out.structure[len(out.structure) - 1] = JSONOutValueEnd
-			} else if underState == JSONOutArray && atom.Typ == AtomTerminal && TerminalValue(atom.data) == ArrayEnd {
+			} else if underState == JSONOutArray && atom.Typ == AtomTerminal && ValueTerminal(atom.data) == ArrayEnd {
 				fmt.Fprint(out.writer, "\n")
 				out.indent(-1)
 				fmt.Fprint(out.writer, "]")
@@ -625,11 +463,11 @@ func ConcatData(first []Atom, second []Atom) []Atom {
 	return res
 }
 
-func Atomise(in []WalkValue) (out []Atom) {
+func Atomise(in []Value) (out []Atom) {
 	numAtoms := 0
 	for _, value := range in {
 		switch v := value.(type) {
-			case TerminalValue, ValueNull, ValueBool, ValueNumber:
+			case ValueTerminal, ValueNull, ValueBool, ValueNumber:
 				numAtoms++
 			case ValueString:
 				numAtoms += utf8.RuneCountInString(string(v)) + 2
@@ -669,11 +507,11 @@ func (err CompoundError) Error() string {
 }
 
 type CompoundResult struct {
-	value WalkValue
+	value Value
 	error error
 }
 
-func Compound(in []Atom) (out []WalkValue, error error) {
+func Compound(in []Atom) (out []Value, error error) {
 	numValues := 0
 	i := 0
 	inString := false
@@ -691,7 +529,7 @@ func Compound(in []Atom) (out []WalkValue, error error) {
 		}
 	}
 	i = 0
-	out = make([]WalkValue, 0, numValues)
+	out = make([]Value, 0, numValues)
 	for {
 		if i >= len(in) {
 			break
@@ -709,7 +547,7 @@ func Compound(in []Atom) (out []WalkValue, error error) {
 				out = append(out, ValueNumber(math.Float64frombits(atom.data)))
 				continue
 			case AtomTerminal:
-				out = append(out, TerminalValue(atom.data))
+				out = append(out, ValueTerminal(atom.data))
 				continue
 			case AtomStringRune:
 				return nil, CompoundRuneOutsideString