console.assert(value[, ...message])

版本历史

版本	变更
v10.0.0	该实现现在符合规范并且不再抛出错误。
v0.1.101	新增于: v0.1.101

value <any> 测试为真的值。
...message <any> 除了 value 之外的所有参数都用作错误消息。

如果 value 为假值或省略，则 console.assert() 写入一条消息。它只写入一条消息，不会影响执行。输出始终以 "Assertion failed" 开头。如果提供，则使用 util.format() 格式化 message。

如果 value 为真值，则什么也不会发生。

console.assert(true, 'does nothing');

console.assert(false, 'Whoops %s work', 'didn\'t');
// Assertion failed: Whoops didn't work

console.assert();
// Assertion failed

History

Version	Changes
v10.0.0	The implementation is now spec compliant and does not throw anymore.
v0.1.101	Added in: v0.1.101

value <any> The value tested for being truthy.
...message <any> All arguments besides value are used as error message.

console.assert() writes a message if value is falsy or omitted. It only writes a message and does not otherwise affect execution. The output always starts with "Assertion failed". If provided, message is formatted using util.format().

If value is truthy, nothing happens.

console.assert(true, 'does nothing');

console.assert(false, 'Whoops %s work', 'didn\'t');
// Assertion failed: Whoops didn't work

console.assert();
// Assertion failed