小编tso*_*orn的帖子

我正在尝试跑步cloud compute os-login ssh-keys add：我明白了

ERROR: (gcloud.compute.os-login.ssh-keys.add) 
User [X] does not have permission to access user [X:importSshPublicKey] (or it may not exist): 
Insufficient IAM permissions. 
The instance belongs to an external organization. 
You must be granted the roles/compute.osLoginExternalUser IAM role 
on the external organization to configure POSIX account information.

其中 X 在两种情况下都是同一用户。如何通过gcloud命令行添加我需要的权限？

我知道如何将 Parquet 文件读入Vec<Row>.

extern crate parquet;
use parquet::file::reader::{FileReader, SerializedFileReader};
use std::{fs, sync::Arc};
use parquet::column::writer::ColumnWriter;
use parquet::{
    file::{
        properties::WriterProperties,
        writer::{FileWriter, SerializedFileWriter},
    },
    schema::parser::parse_message_type,
    schema::types::TypePtr
};
use parquet::record::Row;
use parquet::record::RowAccessor;
use std::fs::File;
use std::io::prelude::*;
use std::path::Path;
use std::path::PathBuf;

fn read_parquet(in_path: &Path) -> (Vec<Row>, TypePtr) {
    // Read Parquet input file. Return a vector of rows and the Schema
    let file = File::open(in_path).unwrap();
    let reader = SerializedFileReader::new(file).unwrap();
    let row_iter = reader.get_row_iter(None).unwrap();
    let num_rows = reader.metadata().file_metadata().num_rows();
    let rows: Vec<Row> = row_iter.collect();
    println!("num …

Otto如何处理不同的事件类？可以有不同的事件类吗？

只有听取特定事件类的听众才会收到通知吗？例如下面的示例是否可以工作,只有A类中的监听器被通知？假设EventClassA并且EventClassB不扩展相同的超类.

class A {
    @Subscribe
    public void handleEvent(EventClassA event)
    {
            //
    }
}

class B {
    @Subscribe
    public void handleEvent(EventClassB event)
    {
            //
    }
}

class C {
    public void postEvent() {
        bus.post(new EventClassA());
    }
}

我正在寻找一些来自Data.Vector包的东西,它的工作concatMap原理与monad一起工作.concatMap有类型...

(a -> Vector b) -> Vector a -> Vector b 

但我正在寻找类型的东西......

(Monad m) => (a -> m (Vector b)) -> Vector a -> m (Vector b)

...或者,特别是以下任何一个:

(MonadRandom m) => ((Int, Int) -> m (Vector Int)) 
                -> Vector (Int, Int) -> m (Vector Int)

(MonadRandom m) => (Int -> Int -> m (Vector Int))
                -> Vector (Int, Int) -> m (Vector Int)

下面的代码应该让我知道我正在尝试做什么,但会产生错误

无法将类型VU.Vector Int与Int
预期类型匹配:m (VU.Vector Int)
实际类型:m (VU.Vector …