gotype: support function types

gotype.go

@@ -1,14 +1,31 @@
 package main
 
+import (
+	"strings"
+)
+
 type gotype struct {
 	SliceOf *gotype
 	MapKey  *gotype
 	MapVal  *gotype
 	PtrTo   *gotype
+
+	IsFunc     bool
+	FuncParams []gotype
+	FuncReturn []gotype
+
 	Plain string
 	// TODO channel-of (although we will never? construct one from PHP source)
 }
 
+func goTypeListToString(gotypes []gotype) string {
+	ret := make([]string, 0, len(gotypes))
+	for _, gt := range gotypes {
+		ret = append(ret, gt.AsGoString())
+	}
+	return strings.Join(ret, `, `)
+}
+
 func (gt gotype) AsGoString() string {
 	if gt.SliceOf != nil {
 		return "[]" + gt.SliceOf.AsGoString()
@@ -19,17 +36,38 @@ func (gt gotype) AsGoString() string {
 	} else if gt.PtrTo != nil {
 		return "*" + gt.PtrTo.AsGoString()
 
+	} else if gt.IsFunc {
+
+		ret := "func(" + goTypeListToString(gt.FuncParams) + `)`
+		if len(gt.FuncReturn) == 1 {
+			ret += ` ` + gt.FuncReturn[0].AsGoString()
+		} else if len(gt.FuncReturn) >= 2 {
+			ret += ` (` + goTypeListToString(gt.FuncReturn) + `)`
+		}
+		return ret
+
 	} else {
 		return gt.Plain
 
 	}
 }
 
+func (gt gotype) IsPlain() bool {
+	if gt.SliceOf != nil || gt.MapKey != nil || gt.PtrTo != nil || gt.IsFunc {
+		return false
+	}
+
+	return true
+}
+
+func (gt gotype) Equals(other *gotype) bool {
+	return gt.AsGoString() == other.AsGoString()
+}
+
 // ZeroValue returns a Go literal string for the zero value of this type.
 func (gt gotype) ZeroValue() string {
-	if gt.SliceOf != nil || gt.MapKey != nil || gt.PtrTo != nil {
-		return `nil` // gt.AsGoString() + "{}"
-
+	if !gt.IsPlain() {
+		return `nil`
 	}
 
 	// It's a plain type

scope.go

@@ -43,11 +43,11 @@ func (this *Scope) Set(Name string, Type gotype) *LocalVar {
 
 	if lv := this.Has(Name); lv != nil {
 		// Update known type for existing variable
-		if lv.Type == unknownVarType {
+		if lv.Type.Equals(&unknownVarType) {
 			lv.Type = Type
-		} else if lv.Type == Type {
+		} else if lv.Type.Equals(&Type) {
 			// no-op, more evidence for the same type
-		} else if lv.Type != Type {
+		} else if !lv.Type.Equals(&Type) {
 			// conflicting type information
 			lv.Type = mixedVarType
 		}