Removed our file.open/file.lines/read/write primitives.

These will be replaced.

**NOTE**: This breaks our examples.

Author: skx

evaluator/stdlib_file.go

@@ -1,40 +1,11 @@
 package evaluator
 
 import (
-	"bufio"
-	"os"
 	"path/filepath"
 
 	"github.com/skx/monkey/object"
 )
 
-//
-// Mapping of file-IDs to file-handles
-//
-var fileHandles = make(map[uintptr]*os.File)
-var fileReaders = make(map[uintptr]*bufio.Reader)
-var fileWriters = make(map[uintptr]*bufio.Writer)
-
-//
-// Horrid hack - setup STDIN/STDOUT/STDERR
-//
-func setupHandles() {
-	if fileHandles[0] != nil {
-		return
-	}
-	fileHandles[0] = os.Stdin
-	fileHandles[1] = os.Stdout
-	fileHandles[2] = os.Stderr
-
-	fileReaders[0] = bufio.NewReader(os.Stdin)
-	fileReaders[1] = bufio.NewReader(os.Stdout)
-	fileReaders[2] = bufio.NewReader(os.Stderr)
-
-	fileWriters[0] = bufio.NewWriter(os.Stdin)
-	fileWriters[1] = bufio.NewWriter(os.Stdout)
-	fileWriters[2] = bufio.NewWriter(os.Stderr)
-}
-
 // array = directory.glob( "/etc/*.conf" )
 func dirGlob(args ...object.Object) object.Object {
 	if len(args) != 1 {
@@ -57,164 +28,9 @@ func dirGlob(args ...object.Object) object.Object {
 	return &object.Array{Elements: result}
 }
 
-// handle = file.open(path)
-func fileOpen(args ...object.Object) object.Object {
-	setupHandles()
-	if len(args) != 1 && len(args) != 2 {
-		return newError("wrong number of arguments. got=%d, want=1|2",
-			len(args))
-	}
-
-	path := args[0].(*object.String).Value
-
-	md := os.O_RDONLY
-	if len(args) == 2 {
-		mode := args[1].(*object.String).Value
-		if mode == "w" {
-			md = os.O_WRONLY
-		}
-
-	}
-	file, err := os.OpenFile(path, os.O_CREATE|md, 0644)
-	if err != nil {
-		return &object.Integer{Value: -1}
-	}
-
-	// convert handle to integer to return it
-	fileHandles[file.Fd()] = file
-
-	// but also store a reader / writer as appropriate
-	if md == os.O_RDONLY {
-		fileReaders[file.Fd()] = bufio.NewReader(file)
-	} else {
-		fileWriters[file.Fd()] = bufio.NewWriter(file)
-	}
-
-	return &object.Integer{Value: int64(file.Fd())}
-}
-
-// file.close(handle)
-func fileClose(args ...object.Object) object.Object {
-	setupHandles()
-	if len(args) != 1 {
-		return newError("wrong number of arguments. got=%d, want=1",
-			len(args))
-	}
-
-	handle := args[0].(*object.Integer).Value
-
-	// If the file was opened for writing then we must flush
-	// it before we close the handle - otherwise our written
-	// data might be lost.
-	if fileWriters[uintptr(handle)] != nil {
-		fileWriters[uintptr(handle)].Flush()
-	}
-	fileHandles[uintptr(handle)].Close()
-	delete(fileHandles, uintptr(handle))
-	delete(fileReaders, uintptr(handle))
-	delete(fileWriters, uintptr(handle))
-	return NULL
-}
-
-// [] = file.lines("path")
-func fileLines(args ...object.Object) object.Object {
-	setupHandles()
-	if len(args) != 1 {
-		return newError("wrong number of arguments. got=%d, want=1",
-			len(args))
-	}
-
-	path := args[0].(*object.String).Value
-	file, err := os.Open(path)
-	if err != nil {
-		return NULL
-	}
-	defer file.Close()
-
-	var lines []string
-	scanner := bufio.NewScanner(file)
-	for scanner.Scan() {
-		lines = append(lines, scanner.Text())
-	}
-
-	// make results
-	l := len(lines)
-	result := make([]object.Object, l, l)
-	for i, txt := range lines {
-		result[i] = &object.String{Value: txt}
-	}
-	return &object.Array{Elements: result}
-}
-
-// str = read(handle)
-func readInput(args ...object.Object) object.Object {
-	setupHandles()
-	if len(args) != 1 {
-		return newError("wrong number of arguments. got=%d, want=1",
-			len(args))
-	}
-
-	id := args[0].(*object.Integer).Value
-	reader := fileReaders[uintptr(id)]
-	if reader == nil {
-		return newError("Reading from an unopened file-handle.")
-	}
-
-	line, err := reader.ReadString('\n')
-	if err == nil {
-		return &object.String{Value: line}
-	}
-	return &object.String{Value: ""}
-}
-
-// write(handle, text)
-func writeOutput(args ...object.Object) object.Object {
-	setupHandles()
-	if len(args) != 2 {
-		return newError("wrong number of arguments. got=%d, want=2",
-			len(args))
-	}
-
-	id := args[0].(*object.Integer).Value
-	txt := args[1].(*object.String).Value
-
-	writer := fileWriters[uintptr(id)]
-	if writer == nil {
-		return newError("Writing to an unopened file-handle.")
-	}
-
-	_, err := writer.Write([]byte(txt))
-	if err == nil {
-		writer.Flush()
-		return &object.Boolean{Value: true}
-	}
-
-	return &object.Boolean{Value: false}
-}
-
 func init() {
 	RegisterBuiltin("directory.glob",
 		func(env *object.Environment, args ...object.Object) object.Object {
 			return (dirGlob(args...))
 		})
-	RegisterBuiltin("read",
-		func(env *object.Environment, args ...object.Object) object.Object {
-			return (readInput(args...))
-		})
-	RegisterBuiltin("write",
-		func(env *object.Environment, args ...object.Object) object.Object {
-			return (writeOutput(args...))
-		})
-	RegisterBuiltin("file.open",
-		func(env *object.Environment, args ...object.Object) object.Object {
-			return (fileOpen(args...))
-		})
-	RegisterBuiltin("file.close",
-		func(env *object.Environment, args ...object.Object) object.Object {
-			return (fileClose(args...))
-		})
-	RegisterBuiltin("file.lines",
-		func(env *object.Environment, args ...object.Object) object.Object {
-			return (fileLines(args...))
-		})
 }