diff --git a/src/Terminal.ts b/src/Terminal.ts
index c5537cc4..e5e3c755 100644
--- a/src/Terminal.ts
+++ b/src/Terminal.ts
@@ -1713,6 +1713,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
    * @param x The column from which to start erasing to the end of the line.
    * @param y The line in which to operate.
    */
+  // FIXME: decide whether to remove from Terminal
   public eraseRight(x: number, y: number): void {
     const line = this.buffer.lines.get(this.buffer.ybase + y);
     if (!line) return;
@@ -1725,6 +1726,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
    * @param x The column from which to start erasing to the start of the line.
    * @param y The line in which to operate.
    */
+  // FIXME: decide whether to remove from Terminal
   public eraseLeft(x: number, y: number): void {
     const line = this.buffer.lines.get(this.buffer.ybase + y);
     if (!line) return;
@@ -1756,6 +1758,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
    * Erase all content in the given line
    * @param y The line to erase all of its contents.
    */
+  // FIXME: decide whether to remove from Terminal
   public eraseLine(y: number): void {
     this.eraseRight(0, y);
   }
diff --git a/src/TerminalLine.test.ts b/src/TerminalLine.test.ts
index e5a57aa5..72cea26d 100644
--- a/src/TerminalLine.test.ts
+++ b/src/TerminalLine.test.ts
@@ -50,4 +50,41 @@ describe('TerminalLine', function(): void {
     chai.expect(ch[CHAR_DATA_WIDTH_INDEX]).equals(NULL_CELL_WIDTH);
     chai.expect(ch[CHAR_DATA_CODE_INDEX]).equals(NULL_CELL_CODE);
   });
+  it('insertCells', function(): void {
+    const line = new TerminalLine();
+    const data: CharData[] = [
+      [1, 'a', 0, 0],
+      [2, 'b', 0, 0],
+      [3, 'c', 0, 0]
+    ];
+    for (let i = 0; i < data.length; ++i) line.push(data[i]);
+    line.insertCells(1, 3, [4, 'd', 0, 0]);
+    chai.expect(line.toArray()).eql([[1, 'a', 0, 0], [4, 'd', 0, 0], [4, 'd', 0, 0]]);
+  });
+  it('deleteCells', function(): void {
+    const line = new TerminalLine();
+    const data: CharData[] = [
+      [1, 'a', 0, 0],
+      [2, 'b', 0, 0],
+      [3, 'c', 0, 0],
+      [4, 'd', 0, 0],
+      [5, 'e', 0, 0]
+    ];
+    for (let i = 0; i < data.length; ++i) line.push(data[i]);
+    line.deleteCells(1, 2, [6, 'f', 0, 0]);
+    chai.expect(line.toArray()).eql([[1, 'a', 0, 0], [4, 'd', 0, 0], [5, 'e', 0, 0], [6, 'f', 0, 0], [6, 'f', 0, 0]]);
+  });
+  it('replaceCells', function(): void {
+    const line = new TerminalLine();
+    const data: CharData[] = [
+      [1, 'a', 0, 0],
+      [2, 'b', 0, 0],
+      [3, 'c', 0, 0],
+      [4, 'd', 0, 0],
+      [5, 'e', 0, 0]
+    ];
+    for (let i = 0; i < data.length; ++i) line.push(data[i]);
+    line.replaceCells(2, 4, [6, 'f', 0, 0]);
+    chai.expect(line.toArray()).eql([[1, 'a', 0, 0], [2, 'b', 0, 0], [6, 'f', 0, 0], [6, 'f', 0, 0], [5, 'e', 0, 0]]);
+  });
 });
diff --git a/src/TerminalLine.ts b/src/TerminalLine.ts
index f88ca1f4..1fd184d6 100644
--- a/src/TerminalLine.ts
+++ b/src/TerminalLine.ts
@@ -10,14 +10,15 @@ import { NULL_CELL_CODE, NULL_CELL_WIDTH, NULL_CELL_CHAR } from './Buffer';
  * Currently the class is a thin proxy to `CharData[]`.
  * Once the storages are in place it will proxy access to
  * typed array based line data.
- * TODO: move typical line actions in `InputHandler` and `Terminal` here:
- *    - create blank line - done
- *    - insert cells - done
- *    - remove cells - done
- *    - maybe Buffer.translateBufferLineToString
- * 
- * next steps towards typed array:
- *    - replace all external push/pop/splice accesses
+ * TODO:
+ *    - move Buffer.translateBufferLineToString here?
+ *    - next steps towards typed array:
+ *        - create ITerminalLine interface w'o length methods
+ *        - resize method
+ *        - replace all external push/pop/splice accesses
+ *        - fixed length
+ *        - remove push/pop/splice
+ *        - implement typed array alternative once string is removed from CharData
  */
 export class TerminalLine {
   static defaultCell: CharData = [0, NULL_CELL_CHAR, NULL_CELL_WIDTH, NULL_CELL_CODE];
@@ -36,21 +37,6 @@ export class TerminalLine {
       for (let i = 0; i < cols; i++) this.push(ch);  // Note: the ctor ch is not cloned
     }
     if (isWrapped) this.isWrapped = true;
-    // for debugging purpose:
-    // throw Error when something tries to do number index access
-    // TODO: remove when done with transition
-    /*
-    for (let i = 0; i < 100; ++i) {
-      Object.defineProperty(this, i.toString(), {
-        get: () => {
-          throw new Error('get per index access is disabled');
-        },
-        set: (value: any) => {
-          throw new Error('set per index access is disabled');
-        }
-      });
-    }
-    */
   }
   get(index: number): CharData {
     return this._data[index];
@@ -59,17 +45,20 @@ export class TerminalLine {
     this._data[index] = data;
     // TODO: unref old, ref new
   }
+  // to be removed for typed array
   pop(): CharData | undefined  {
     // TODO: unref here, change CharData to [typeof Attributes, ...]
     const data = this._data.pop();
     this.length = this._data.length;
     return data;
   }
+  // to be removed for typed array
   push(data: CharData): void {
     this._data.push(data);
     this.length = this._data.length;
     // TODO: ref here
   }
+  // to be removed for typed array
   splice(start: number, deleteCount: number, ...items: CharData[]): CharData[] {
     const removed = this._data.splice(start, deleteCount, ...items);
     this.length = this._data.length;