added documentation and did some slight restructuring. it's party time.

nexgb/xgbgen/xml_fields.go

@@ -1,31 +1,10 @@
 package main
 
-/*
-	A series of fields should be taken as "structure contents", and *not*
-	just the single 'field' elements. Namely, 'fields' subsumes 'field'
-	elements.
-
-	More particularly, 'fields' corresponds to list, in order, of any of the
-	follow elements: pad, field, list, localfield, exprfield, valueparm
-	and switch.
-
-	Thus, the 'Field' type must contain the union of information corresponding
-	to all aforementioned fields.
-
-	This would ideally be a better job for interfaces, but I could not figure
-	out how to make them jive with Go's XML package. (And I don't really feel
-	up to type translation.)
-*/
-
 import (
 	"encoding/xml"
-	"fmt"
 	"log"
-	"strings"
 )
 
-type XMLFields []*XMLField
-
 type XMLField struct {
 	XMLName xml.Name
 
@@ -47,7 +26,7 @@ type XMLField struct {
 	ValueListName string `xml:"value-list-name,attr"`
 
 	// For 'switch' element.
-	Bitcases XMLBitcases `xml:"bitcase"`
+	Bitcases []*XMLBitcase `xml:"bitcase"`
 
 	// I don't know which elements these are for. The documentation is vague.
 	// They also seem to be completely optional.
@@ -56,41 +35,6 @@ type XMLField struct {
 	OptAltEnum string `xml:"altenum,attr"`
 }
 
-// String is for debugging purposes.
-func (f *XMLField) String() string {
-	switch f.XMLName.Local {
-	case "pad":
-		return fmt.Sprintf("pad (%d bytes)", f.Bytes)
-	case "field":
-		return fmt.Sprintf("field (type = '%s', name = '%s')", f.Type, f.Name)
-	case "list":
-		return fmt.Sprintf("list (type = '%s', name = '%s', length = '%s')",
-			f.Type, f.Name, f.Expr)
-	case "localfield":
-		return fmt.Sprintf("localfield (type = '%s', name = '%s')",
-			f.Type, f.Name)
-	case "exprfield":
-		return fmt.Sprintf("exprfield (type = '%s', name = '%s', expr = '%s')",
-			f.Type, f.Name, f.Expr)
-	case "valueparam":
-		return fmt.Sprintf("valueparam (type = '%s', name = '%s', list = '%s')",
-			f.ValueMaskType, f.ValueMaskName, f.ValueListName)
-	case "switch":
-		bitcases := make([]string, len(f.Bitcases))
-		for i, bitcase := range f.Bitcases {
-			bitcases[i] = bitcase.StringPrefix("\t")
-		}
-		return fmt.Sprintf("switch (name = '%s', expr = '%s')\n\t%s",
-			f.Name, f.Expr, strings.Join(bitcases, "\n\t"))
-	default:
-		log.Panicf("Unrecognized field element: %s", f.XMLName.Local)
-	}
-
-	panic("unreachable")
-}
-
-type XMLBitcases []*XMLBitcase
-
 // Bitcase represents a single expression followed by any number of fields.
 // Namely, if the switch's expression (all bitcases are inside a switch),
 // and'd with the bitcase's expression is equal to the bitcase expression,
@@ -100,7 +44,7 @@ type XMLBitcases []*XMLBitcase
 // it's the closest thing to a Union I can get to in Go without interfaces.
 // Would an '<expression>' tag have been too much to ask? :-(
 type XMLBitcase struct {
-	Fields XMLFields `xml:",any"`
+	Fields []*XMLField `xml:",any"`
 
 	// All the different expressions.
 	// When it comes time to choose one, use the 'Expr' method.
@@ -114,17 +58,6 @@ type XMLBitcase struct {
 	ExprPop   *XMLExpression `xml:"popcount"`
 }
 
-// StringPrefix is for debugging purposes only.
-// StringPrefix takes a string to prefix to every extra line for formatting.
-func (b *XMLBitcase) StringPrefix(prefix string) string {
-	fields := make([]string, len(b.Fields))
-	for i, field := range b.Fields {
-		fields[i] = fmt.Sprintf("%s%s", prefix, field)
-	}
-	return fmt.Sprintf("%s\n\t%s%s", b.Expr(), prefix,
-		strings.Join(fields, "\n\t"))
-}
-
 // Expr chooses the only non-nil Expr* field from Bitcase.
 // Panic if there is more than one non-nil expression.
 func (b *XMLBitcase) Expr() *XMLExpression {