Move reading and writing of tokens into a separate package to prepare for other input and output formats

1 files changed, 1 insertions, 134 deletions

diff --git a/walk/walk.go b/walk/walk.go
index 6e86877..1073c67 100644
--- a/walk/walk.go
+++ b/walk/walk.go
@@ -1,18 +1,14 @@
 package walk
 
 import (
-	"fmt"
 	"strings"
 	"math"
 	"unicode/utf8"
-	"bufio"
 )
 
 // int or string
 type PathSegment interface {}
-func stringPathSegment(segment PathSegment) string {
-	return fmt.Sprintf("%v", segment)
-}
+
 type Path []PathSegment
 func (path Path) ToWalkValues() []Value {
 	var values []Value
@@ -49,135 +45,6 @@ type WalkItem struct {
 	Path []Atom
 }
 
-type JSONOutStructure int
-const (
-	JSONOutRoot JSONOutStructure = iota
-	JSONOutMap
-	JSONOutArray
-	JSONOutString
-	JSONOutValueEnd
-)
-
-type JSONOut struct {
-	structure []JSONOutStructure
-	writer *bufio.Writer
-}
-
-func (out *JSONOut) indent(adjust int) {
-	fmt.Fprint(out.writer, strings.Repeat("\t", len(out.structure) - 1 + adjust))
-}
-
-func (out *JSONOut) atomOut(key string, atom Atom) {
-	state := out.structure[len(out.structure) - 1]
-	switch state {
-		case JSONOutRoot, JSONOutMap, JSONOutArray:
-			switch atom.Typ {
-				case AtomNull, AtomBool, AtomNumber:
-					out.indent(0)
-					if state == JSONOutMap {
-						fmt.Fprintf(out.writer, "%q: ", key)
-					}
-					fmt.Fprint(out.writer, atom.String())
-					out.structure = append(out.structure, JSONOutValueEnd)
-				case AtomStringTerminal:
-					out.indent(0)
-					if state == JSONOutMap {
-						fmt.Fprintf(out.writer, "%q: ", key)
-					}
-					fmt.Fprint(out.writer, "\"")
-					out.structure = append(out.structure, JSONOutString)
-				case AtomTerminal:
-					switch ValueTerminal(atom.data) {
-						case MapBegin:
-							out.indent(0)
-							if state == JSONOutMap {
-								fmt.Fprintf(out.writer, "%q: ", key)
-							}
-							fmt.Fprint(out.writer, "{\n")
-							out.structure = append(out.structure, JSONOutMap)
-						case ArrayBegin:
-							out.indent(0)
-							if state == JSONOutMap {
-								fmt.Fprintf(out.writer, "%q: ", key)
-							}
-							fmt.Fprint(out.writer, "[\n")
-							out.structure = append(out.structure, JSONOutArray)
-						case MapEnd:
-							out.indent(-1)
-							if state != JSONOutMap {
-								panic("Map ended while not inside a map")
-							}
-							fmt.Fprint(out.writer, "}")
-							out.structure[len(out.structure) - 1] = JSONOutValueEnd
-						case ArrayEnd:
-							out.indent(-1)
-							if state != JSONOutArray {
-								panic("Array ended while not inside a array")
-							}
-							fmt.Fprint(out.writer, "]")
-							out.structure[len(out.structure) - 1] = JSONOutValueEnd
-						default:
-							panic("Invalid TerminalValue")
-					}
-				default:
-					panic("Invalid AtomType in root value")
-			}
-		case JSONOutValueEnd:
-			out.structure = out.structure[:len(out.structure) - 1]
-			underState := out.structure[len(out.structure) - 1]
-			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 && ValueTerminal(atom.data) == ArrayEnd {
-				fmt.Fprint(out.writer, "\n")
-				out.indent(-1)
-				fmt.Fprint(out.writer, "]")
-				out.structure[len(out.structure) - 1] = JSONOutValueEnd
-			} else if underState == JSONOutRoot {
-				panic("Tried to output JSON after root value has concluded")
-			} else {
-				fmt.Fprint(out.writer, ",\n")
-				out.atomOut(key, atom)
-			}
-		case JSONOutString:
-			if atom.Typ == AtomStringTerminal {
-				fmt.Fprint(out.writer, "\"")
-				out.structure[len(out.structure) - 1] = JSONOutValueEnd
-			} else {
-				fmt.Fprint(out.writer, atom.String())
-			}
-		default:
-			panic("Invalid JSONOutState")
-	}
-}
-
-func (out *JSONOut) Print(path Path, values []Atom) {
-	var segment PathSegment
-	if len(path) > 0 {
-		segment = path[len(path) - 1]
-	}
-	segmentString := stringPathSegment(segment)
-	for _, atom := range values {
-		out.atomOut(segmentString, atom)
-	}
-}
-
-func (out *JSONOut) AssertDone() {
-	out.writer.Flush()
-	if len(out.structure) != 2 || out.structure[0] != JSONOutRoot || out.structure[1] != JSONOutValueEnd {
-		panic("Program ended with incomplete JSON output")
-	}
-}
-
-func NewJSONOut(writer *bufio.Writer) JSONOut {
-	return JSONOut {
-		structure: []JSONOutStructure{JSONOutRoot},
-		writer: writer,
-	}
-}
-
 func ConcatData(first []Atom, second []Atom) []Atom {
 	res := make([]Atom, 0, len(first) + len(second))
 	res = append(res, first...)