mapping

问题 I have a map of form shown below: Map = #{#{country=>"India"} => #{rank => 1}}. I am trying to match it as follows: 1. #{Key := V} = Map. OR 2. #{#{country := Country} := #{rank := Rank}} = Map. But its not working for me. Any help as to how it can be done? 回答1: When matching key-value associations from maps the key expression must be an expression with literals or bound variables, see the documentation of maps (section Maps in Patterns ). The problem with a match expression like: #{Key := V}

问题 I'm retrieving firebase data back as a dictionary of dictionary: guard let data = snapshot.value as? [String: [String:Int]] else { And I'm trying to retrieve the first key(?) as in if it comes back as a result like this: "café-veritas": ["AmpleSeating": 1, "Organic": 1, "Quiet": 1, "AmpleOutletAccess": 1, "Couch": 1, "Loud": 1, "GlutenFree": 1, "FreeWifi": 1], "cafe-myriade": ["Terasse": 1, "LaptopFriendly": 1, "Quiet": 1, "FreeWifi": 1, "FastWifi ": 1, "GlutenFree": 1], I'm trying to put the

问题 I am looking for a framework or a solution that maps the column names of a database to variables of a Java object. Lets say I have a xml file that contains the element "docid" and its value. The database would contain a table with one column called "ducumentID". I want to compare the two values, so the one value inside the "docid" tag from the xml file and the data entry of the column "docid". Because in this example its just one thing I have to compare it would be easy to do this comparision

问题 I have several (albeit related) questions about Spring MVC RequestMapping configuration: Say I have a type-level RequestMapping annotation as follows: @RequestMapping("/root/") . What is the difference between adding this method-level RequestMapping: @RequestMapping(value="leaf") and that one: @RequestMapping(value="/leaf") ? Notice the leading slash in second method-level mapping. What is the difference between having this type-level RequestMapping: @RequestMapping("/root/") and that one

问题 I am using a mapping file that contains the Entity and the Column Names to perform the insert on so can this be done with entity framework ? The alternative version is just to use inline SQL and write code like sql = INSERT INTO " + someTable + etc.... 回答1: I don't think using Entity Framework (EF) will be a good fit for this project you're working on. One of the main benefits of using EF is the object graph; it takes care of recognizing new records, updated records and so on. If you are

问题 I am new to react, so I am not sure how to call it. As a result, I apologize if this question was asked before. What I probably want to do is maping data, but I am not sure how to do it. componentDidMount() { fetch("https://reqres.in/api/users?page=3") .then(data => {return data.json()}) .then(datum => this.setState({client:datum.data})); } Above is my fetch component. The data that is taken from the API include the id, lastname, firstname. However, I want to assign id as slug instead and

问题 I am new to react, so I am not sure how to call it. As a result, I apologize if this question was asked before. What I probably want to do is maping data, but I am not sure how to do it. componentDidMount() { fetch("https://reqres.in/api/users?page=3") .then(data => {return data.json()}) .then(datum => this.setState({client:datum.data})); } Above is my fetch component. The data that is taken from the API include the id, lastname, firstname. However, I want to assign id as slug instead and

问题 I got stuck on a maybe simple task, but could not find any solution. I have some JSON Data - lets say: [{ "_id": 1, "type": "person", "Name": "Hans", "WorksFor": ["3", "4"] }, { "_id": 2, "type": "person", "Name": "Michael", "WorksFor": ["3"] }, { "_id": 3, "type": "department", "Name": "Marketing" }, { "_id": 4, "type": "department", "Name": "Sales" }] As I learned here it is quite simple to get all the persons and the departments they work for together using a map array for the departments.

问题 Having something like: @Getter @Setter public static class Entity { private int hash; private LocalDateTime createdTime; } and @Getter @Setter public static class DTO { private String hash; private String createdTime; } I need birectional mapping so I should be able to map Entity -> DTO -> Entity . In this example the property type happens to be LocalDateTime but could be any type that needs parsing from String or so (just to say that I am not after better way to map LocalDateTime but in

问题 I'd like to persist some JSON to elastic(search) that looks a little like this: { "name": "value", "points": [ { "lat": 0.0, "lon": 0.0 }, { "lat": 1.0, "lon": 1.0 } ] } Points being a list of the type geo_point in elastic. Because they're geo_point values I need to define the index mapping, but the closest I can see is to do this: "place": { "properties": { "name": { "type": "string" }, "points": { "properties": { "location": { "type": "geo_point" } } } } } Which would mean having each point