Refactor interfaces names

Author: katcipis

internal/sh/builtin/len.go

@@ -10,7 +10,7 @@ import (
 
 type (
 	lenFn struct {
-		arg sh.Enumerable
+		arg sh.Collection
 	}
 )
 
@@ -38,11 +38,11 @@ func (l *lenFn) SetArgs(args []sh.Obj) error {
 	}
 
 	obj := args[0]
-	indexer, err := sh.NewEnumerable(obj)
+	col, err := sh.NewCollection(obj)
 	if err != nil {
 		return errors.NewError("len:error[%s]", err)
 	}
 
-	l.arg = indexer
+	l.arg = col
 	return nil
 }

internal/sh/shell.go

@@ -546,12 +546,12 @@ func (shell *Shell) setvar(name *ast.NameNode, value sh.Obj) error {
 		return err
 	}
 
-	indexer, err := sh.NewWriteIndexer(obj)
+	col, err := sh.NewWriteableCollection(obj)
 	if err != nil {
 		return errors.NewEvalError(shell.filename, name, err.Error())
 	}
 
-	err = indexer.Set(index, value)
+	err = col.Set(index, value)
 	if err != nil {
 		return errors.NewEvalError(
 			shell.filename,
@@ -1482,7 +1482,7 @@ func (shell *Shell) evalIndexedVar(indexVar *ast.IndexExpr) (sh.Obj, error) {
 		return nil, err
 	}
 
-	indexer, err := sh.NewReadIndexer(v)
+	col, err := sh.NewCollection(v)
 	if err != nil {
 		return nil, errors.NewEvalError(shell.filename, indexVar.Var, err.Error())
 	}
@@ -1492,7 +1492,7 @@ func (shell *Shell) evalIndexedVar(indexVar *ast.IndexExpr) (sh.Obj, error) {
 		return nil, err
 	}
 
-	val, err := indexer.Get(indexNum)
+	val, err := col.Get(indexNum)
 	if err != nil {
 		return nil, errors.NewEvalError(shell.filename, indexVar.Var, err.Error())
 	}
@@ -1505,7 +1505,7 @@ func (shell *Shell) evalArgIndexedVar(indexVar *ast.IndexExpr) ([]sh.Obj, error)
 		return nil, err
 	}
 
-	indexer, err := sh.NewReadIndexer(v)
+	col, err := sh.NewCollection(v)
 	if err != nil {
 		return nil, errors.NewEvalError(shell.filename, indexVar.Var, err.Error())
 	}
@@ -1515,7 +1515,7 @@ func (shell *Shell) evalArgIndexedVar(indexVar *ast.IndexExpr) ([]sh.Obj, error)
 		return nil, err
 	}
 
-	retval, err := indexer.Get(indexNum)
+	retval, err := col.Get(indexNum)
 	if err != nil {
 		return nil, errors.NewEvalError(shell.filename, indexVar.Var, err.Error())
 	}
@@ -2196,14 +2196,14 @@ func (shell *Shell) executeFor(n *ast.ForNode) ([]sh.Obj, error) {
 		return nil, err
 	}
 
-	indexer, err := sh.NewReadIndexer(obj)
+	col, err := sh.NewCollection(obj)
 	if err != nil {
 		return nil, errors.NewEvalError(shell.filename,
 			inExpr, "error[%s] trying to iterate", err)
 	}
 
-	for i := 0; i < indexer.Len(); i++ {
-		val, err := indexer.Get(i)
+	for i := 0; i < col.Len(); i++ {
+		val, err := col.Get(i)
 		if err != nil {
 			return nil, errors.NewEvalError(shell.filename,
 				inExpr, "unexpected error[%s] during iteration", err)

sh/obj.go

@@ -32,44 +32,29 @@ type (
 		runes []rune
 	}
 
-	Enumerable interface {
+	Collection interface {
 		Len() int
+		Get(index int) (Obj, error)
 	}
 
-	WriteIndexer interface {
+	WriteableCollection interface {
 		Set(index int, val Obj) error
 	}
-
-	ReadIndexer interface {
-		Enumerable
-		Get(index int) (Obj, error)
-	}
 )
 
-func NewEnumerable(o Obj) (Enumerable, error) {
-	sizer, ok := o.(Enumerable)
+func NewCollection(o Obj) (Collection, error) {
+	sizer, ok := o.(Collection)
 	if !ok {
 		return nil, fmt.Errorf(
-			"SizeError: trying to get size from a non enumerable type %s",
+			"SizeError: trying to get size from type %s which is not a collection",
 			o.Type(),
 		)
 	}
 	return sizer, nil
 }
 
-func NewReadIndexer(o Obj) (ReadIndexer, error) {
-	indexer, ok := o.(ReadIndexer)
-	if !ok {
-		return nil, fmt.Errorf(
-			"IndexError: trying to use a non read/indexable type %s to read from index",
-			o.Type(),
-		)
-	}
-	return indexer, nil
-}
-
-func NewWriteIndexer(o Obj) (WriteIndexer, error) {
-	indexer, ok := o.(WriteIndexer)
+func NewWriteableCollection(o Obj) (WriteableCollection, error) {
+	indexer, ok := o.(WriteableCollection)
 	if !ok {
 		return nil, fmt.Errorf(
 			"IndexError: trying to use a non write/indexable type %s to write on index: ",