Use instructions for the console.warn method in node.js

Method description:

This method is the same as console.error(). As you can see from the source code, console.error is actually a direct call to console.warn

Grammar:

console.warn([data], [...])

Receiving parameters:

Console.log takes several parameters, and if there is only one parameter, it outputs the string form of that parameter.

If there are more than one argument, the output is in a format similar to the C printf() command.

If there are no arguments, only a newline character is printed

Example:

var count = 1234; 

console.error('count: %d', count);

Source:

Console.prototype.warn = function() {

  this._stderr.write(util.format.apply(this, arguments) + 'n');

};