tools/dom/templates/html/dart2js/impl_ArrayBuffer.darttemplate

// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of $LIBRARYNAME;

$(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
$!MEMBERS
  @DomName('ArrayBuffer.slice')
  ArrayBuffer slice(int begin, [int end]) {
    // IE10 supports ArrayBuffers but does not have the slice method.
    if (JS('bool', '!!#.slice', this)) {
      if (?end) {
        return JS('ArrayBuffer', '#.slice(#, #)', this, begin, end);
      }
      return JS('ArrayBuffer', '#.slice(#)', this, begin);
    } else {
      var start = begin;
      // Negative values go from end.
      if (start < 0) {
        start = this.byteLength + start;
      }
      var finish = ?end ? min(end, byteLength) : byteLength;
      if (finish < 0) {
        finish = this.byteLength + finish;
      }
      var length = max(finish - start, 0);

      var clone = new Int8Array(length);
      var source = new Int8Array.fromBuffer(this, start);
      for (var i = 0; i < length; ++i) {
        clone[i] = source[i];
      }
      return clone.buffer;
    }
  }
}