pattern-matching

问题 Hi i am tring to move with this below formatted text input: NICK JEFF NOAA A4:80:15 NOAA A4:80:17 NOOI D0:F2:0B BASE-TREE_IN-M_K NICK STAN NOAA C1:46:6B NOOI D5:75:0C BASE-TREE_OUT_OUT NICK INDEXER NOOI D5:75:0C SEAT_25 NOAA C1:46:6B NICK VUZER NOAA A4:F2:CD NOOI D0:F2:2D SEAT_42_FLIGHT NOAA A4:F2:CD NICK CAPTAIN NOOI A4:82:8D NOAA A4:82:8F NOOI 40:63:07 SYS-BRAVO_X1 NOOI 40:62:DB SYS-BRAVO_X2 NOOI 40:62:B5 SYS-BRAVO_X3 NOOI D0:47:4A BASE-TREE_OUT_OUT NOOI 51:30:45 NOBASE-INDEX_OUT_FIF NOOI

问题 I'm taking some predefined semantic rules and implementing them as an interpreter for the lettuce language using Scala. In Multi-Let, I'm trying to update an environment variable using two lists. I'm sort of new to Scala so I'm not too sure how to do this without converting the environment variable to a List. Is there a way to manipulate the return type in my zip function? I'm getting the following error message. My goal is to get a single updated map rather than a list of updated maps. cmd2

问题 I'm having issues with understanding how matching types in generic functions work in swift. I do not understand why my code is not compiling. This is what I have: enum LoadingState<T> { case idle case loading case failed(Error) case loaded(T) } private func updateInternal(_ state: Int) { print("=int") } private func updateInternal(_ state: String) { print("=string") } private func update<T>(_ state: LoadingState<T>) { switch state { case .loaded(let viewModel): updateInternal(viewModel)

问题 I'm having issues with understanding how matching types in generic functions work in swift. I do not understand why my code is not compiling. This is what I have: enum LoadingState<T> { case idle case loading case failed(Error) case loaded(T) } private func updateInternal(_ state: Int) { print("=int") } private func updateInternal(_ state: String) { print("=string") } private func update<T>(_ state: LoadingState<T>) { switch state { case .loaded(let viewModel): updateInternal(viewModel)

问题 I need to refer to a value deep within a structure which includes an Option nested in a struct property, nested in a Result . My current (working) solution is: let raw = &packet[16..]; match PacketHeaders::from_ip_slice(raw) { Err(_value) => { /* ignore */ }, Ok(value) => { match value.ip { Some(Version4(header)) => { let key = format!("{}.{}.{}.{},{}.{}.{}.{}", header.source[0], header.source[1], header.source[2], header.source[3], header.destination[0], header.destination[1], header

问题 I have a database in postgresql called mydata with a field called text. I'm interested in doing regex pattern matching and only returning the snippet of the match, not the entire text. I know you can use pg_trgm (creates a trigram matching index) to speed up the search, but is there a way to do both the searching and matching as a combined statement? I'll provide some context: CREATE EXTENSION pg_trgm; CREATE INDEX text_trgm_idx ON mydata USING GIN(text gin_trgm_ops); I'll use the example

问题 This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center. Closed 8 years ago . I'm trying to modify and update an old Greasemonkey script with the goal of automatically adding an affiliate ID to all Amazon links. I'm a novice when

问题 I am trying to understand parse tree matching in ANTLR 4, so for that I have the following java code: package sampleCodes; public class fruits { public static void main(String[] args){ int a = 10; System.out.println(a); } } I am using ANTLR 4 to create a parse tree of this code. Now, I want to use tree pattern matching function to find "int a = 10;". There is a doc on GitHub: https://github.com/antlr/antlr4/blob/master/doc/tree-matching.md which explains this(something like this) by an

问题 I'm trying to iterate through all the 'FindMe' nodes but I'm struggling with the pattern matching. This is going to be used as a plugin in another piece of software so I'm trying to avoid using a parsing library. Given the following xml <?xml version="1.0" encoding="utf-8"?> <NodeA> <NodeB> <FindMe attr="1"> <NodeC attr="1" /> </FindMe> <FindMe attr="2"> <NodeC attr="2" /> </FindMe> </NodeB> </NodeA> When I try this it only prints the last match for k, _ in src:gmatch(".+(<FindMe .+</FindMe>)

问题 Scala beginner here, I'm trying to find all the tweets text that contain at least one keyword in the list of keywords given. Where a tweet: case class Tweet(user: String, text: String, retweets: Int) With an example Tweet("user1", "apple apple", 3) Given that wordInTweet should return true if at least one keyword in the list keywords can be found in the tweet's text. I tried implementing it like the following: def wordInTweet(tweet: Tweet, keywords: List[String]): Boolean = { keywords.exists