有没有办法在函数中使用多于两个参数的函数?一个例子是node的fs.read,其中回调的三个参数是err,bytes和data.data参数不会传递给then函数,因此这会记录undefined:
var fs = require('fs');
var Promise = require('bluebird');
var open = Promise.promisify(fs.open);
var read = Promise.promisify(fs.read);
open('test.txt', 'r')
.then(function(fd) {
var buffer = new Buffer(1024);
read(fd, buffer, 0, buffer.length, null).then(function(bytes, data) {
console.log(data);
});
});
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