Fix import handling. Handle multiple packages per directory and save

each output package to a different file.

.gitignore

@@ -1,3 +1,4 @@
 test/basic/basic
 test/basic/pgen.go
+test/basic/pgen_aaa.go
 test/basic/db

cmd/pgen/gen.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"path/filepath"
 	"log"
 	"go/ast"
 	"go/format"
@@ -9,6 +10,7 @@ import (
 	"golang.org/x/tools/go/ast/astutil"
 	"os"
 	"regexp"
+	"strings"
 )
 
 type subspec struct {
@@ -22,6 +24,7 @@ type Generator struct{
 	fspec, tspec, nspec subspec
 	nspecs []subspec
 	nodes *ast.File
+	name string
 }
 
 func subs(dst *string, specs []subspec) {
@@ -83,17 +86,33 @@ func (g *Generator) Visit(node ast.Node) ast.Visitor {
 	return g
 }
 
+var (
+	qexp *regexp.Regexp
+)
+
 func init() {
-	err := os.Remove("pgen.go")
-	if err != nil && os.IsExist(err) {
-		log.Fatal("Removing pgen.go:",err)
+	fs,err := filepath.Glob("pgen*.go")
+	if err != nil {
+		log.Fatal("Glob error")
 	}
+	for _,f := range(fs) {
+		err := os.Remove(f)
+		if err != nil && os.IsExist(err) {
+			log.Fatal("Removing ",f,err)
+		}
+	}
+	qexp = regexp.MustCompile(`"`)
 }
 
-func NewGenerator() *Generator {
+func NewGenerator(ns ...string) *Generator {
 	g := &Generator{}
 	g.firstone = true
 	g.fset = token.NewFileSet()
+	if len(ns) > 0 {
+		g.name = ns[0]
+	} else {
+		g.name = "main"
+	}
 	return g
 }
 
@@ -124,24 +143,29 @@ func (g *Generator) Add(newName, typName, typ string) {
 	g.firstone = false
 }
 
-func (g *Generator) Import(imports map[string]bool) {
+func (g *Generator) Import(name string) {
 	if g.nodes == nil {
 		return
 	}
 
 	// strip quotation marks from imports
-	qexp := regexp.MustCompile(`"`)
-	for v := range imports {
-		v = qexp.ReplaceAllString(v,"")
-		astutil.AddImport(g.fset, g.nodes, v)
-	}
+	name = qexp.ReplaceAllString(name,"")
+	astutil.AddImport(g.fset, g.nodes, name)
 }
 
 func (g *Generator) Save() {
 	if g.nodes == nil {
 		return
 	}
-	of, err := os.Create("pgen.go")
+	var of *os.File
+	var err error
+	if g.name == "main" {
+		of, err = os.Create("pgen.go")
+	} else {
+		oname := strings.Join([]string{"pgen_",g.name,".go"},"")
+		of, err = os.Create(oname)
+		g.nodes.Name = ast.NewIdent(g.name)
+	}
 	if err != nil {
 		log.Fatal("Cannot open pgen.go")
 	}

cmd/pgen/main.go

@@ -113,13 +113,16 @@ func main() {
 	}
 	// run type checker on each package
 	for _,pkg := range pkgs {
+		log.Print("Processing package ",pkg.Name)
 		ts = make(map[string]tps)
 		chkpkg(pkg)
-		g := NewGenerator()
+		g := NewGenerator(pkg.Name)
 		for _,v := range ts {
 			g.Add(v.fun, v.name, v.typ)
 		}
-		g.Import(needImps)
+		for name := range needImps {
+			g.Import(imps[name])
+		}
 		// process template for each type identified and
 		// generate output
 		g.Save()

test/basic/other.go

@@ -0,0 +1,7 @@
+package aaa
+
+func Hi() {
+	y := persistFoo("y",7)
+	_ = y
+}
+