小编Chr*_*kai的帖子

无论如何,我可以将HTML5输入类型='datetime-local'的默认值设置为今天的日期和当前时间.

谢谢你

测试此功能的最佳方法是什么

export function receivingItems() {
  return (dispatch, getState) => {
    axios.get('/api/items')
      .then(function(response) {
        dispatch(receivedItems(response.data));
      });
  };
}

这是我现在拥有的

describe('Items Action Creator', () => {
  it('should create a receiving items function', () => {
    expect(receivingItems()).to.be.a.function;
  });
});

我有来自Jasmine.js的这个测试once函数的规范.我不知道如何实现这样的功能.

/* Functions that decorate other functions.  These functions return a version of the function
   with some changed behavior. */

// Given a function, return a new function will only run once, no matter how many times it's called
describe("once", function() {
  it("should only increment num one time", function() {
    var num = 0;
    var increment = once(function() {
      num++;
    });
    increment();
    increment();

    expect(num).toEqual(1);
  });
});

我不太明白我该怎么做.我知道我应该做一次函数(myFunction){}但除此之外,我被困住了.我发现这与封闭有关,仍然无法绕过它.

我希望用户输入1-100之间的数字,直到用户输入有效数字,循环将继续说"输入无效".

我的代码如下.我哪里做错了？

// Initialize var userGuess
var userGuess;

// I want to make the prompt keep asking a number between 1-100, if it doesn't satisfy the requirement, it will keep asking
for (var valid = false; valid == true;) {
    userGuess = prompt("Guess a number");
    if ((userGuess >= 1) && (userGuess <= 100)) {
        valid = true;
    } else {
        valid = false;
        console.log("That number is invalid! Please enter a number between 1-100");
    }
}

下面的代码适用于SELECT语句:

WITH 
  smaller_uuid AS (
    SELECT
      id, uuid, email, first_name, last_name, display_name
    FROM stack_users_production.users AS user1
    WHERE EXISTS (
      SELECT
        id, uuid, email
      FROM
        stack_users_production.users AS user2
      WHERE
        user1.id = user2.id AND
        user1.email = user2.email AND
        user1.uuid < user2.uuid
    )
  )

SELECT 
  id, uuid, email, first_name, last_name, display_name
FROM 
  stack_users_production.users
WHERE
  uuid IN (SELECT uuid FROM smaller_uuid);

但是下面的代码不适用于DELETE语句:

WITH 
  smaller_uuid AS (
    SELECT
      id, uuid, email, first_name, last_name, display_name
    FROM stack_users_production.users AS user1
     WHERE EXISTS (
      SELECT
        id, uuid, email …

有人想解释这个语法在Ruby中意味着什么吗？

class Animal
  def name_category
    @animals ||={}
  end
end

另外,有没有办法在不使用attr_accessor,attr_reader,attr_writer或def initialize的情况下设置对象变量？