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// 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.
/// dart2js "primitives", that is, features that cannot be implemented without
/// access to JavaScript features.
library dart2js._js_primitives;
import 'dart:_foreign_helper' show JS;
/**
* This is the low-level method that is used to implement [print]. It is
* possible to override this function from JavaScript by defining a function in
* JavaScript called "dartPrint".
*
* Notice that it is also possible to intercept calls to [print] from within a
* Dart program using zones. This means that there is no guarantee that a call
* to print ends in this method.
*/
void printString(String string) {
if (JS<bool>('!', r'typeof dartPrint == "function"')) {
// Support overriding print from JavaScript.
JS('void', r'dartPrint(#)', string);
return;
}
// Inside browser or nodejs.
if (JS<bool>('!', r'typeof console == "object"') &&
JS<bool>('!', r'typeof console.log != "undefined"')) {
JS('void', r'console.log(#)', string);
return;
}
// Don't throw inside IE, the console is only defined if dev tools is open.
if (JS<bool>('!', r'typeof window == "object"')) {
return;
}
// Running in d8, the V8 developer shell, or in Firefox' js-shell.
if (JS<bool>('!', r'typeof print == "function"')) {
JS('void', r'print(#)', string);
return;
}
// This is somewhat nasty, but we don't want to drag in a bunch of
// dependencies to handle a situation that cannot happen. So we
// avoid using Dart [:throw:] and Dart [toString].
JS('void', 'throw "Unable to print message: " + String(#)', string);
}