Add vertex class for javascript and typescript

[zhuoqinyue]

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1 Ignored Deployment

Name	Status	Preview	Comments	Updated
hello-algo	⬜️ Ignored (Inspect)			Feb 19, 2023 at 5:10AM (UTC)

[krahets]

Hi @zhuoqinyue ! The Vertex class is used for the adjacency list implementation. Could you update the adjacency_list.js and ...ts referring to the Java code. Thanks!

[zhuoqinyue]

Hi @zhuoqinyue ! The Vertex class is used for the adjacency list implementation. Could you update the adjacency_list.js and ...ts referring to the Java code. Thanks!

OK. But there will cause a problem when I write the code of graph_bfs.
The module.exports of js will cause other code in adjacency_list.js to execute. (B
ecause I need to import adjacency_list to finish graph_bfs)
Then the execution result of adjacency_list.js will be output first, and then graph_bfs will be executed.

Do you think this problem has a big impact?

[krahets]

Yes. We'd better solve this. @justin-tse How do you think about it?

[zhuoqinyue]

I have a opinion that we don't have to update the adjacency_list.js.
And just write a new adjacency_list class in the javascript/include folder.

[krahets]

Yes. But it is not elegant because we will make a twin class.

Is there an entry point check in JS and TS? Like if __name__ == "__main__": in Python.

• When running this file, the test case will be executed.
• When importing this file as a module, the test case will NOT be executed.

[zhuoqinyue]

It seems there no such method.

[zhuoqinyue]

emm... One more solution.
Create a main function to wrap these test cases, and then don't execute the main function.
Let the user execute it by himself @krahets

[krahets]

Better but not enough elegant haha!

[zhuoqinyue]

I've updated the adjacency_list @krahets

[justin-tse]

Yes. But it is not elegant because we will make a twin class.

Is there an entry point check in JS and TS? Like if __name__ == "__main__": in Python.

• When running this file, the test case will be executed.
• When importing this file as a module, the test case will NOT be executed.

@zhuoqinyue Thank you for the clear codes. @krahets I think we can use require.main to solve this problem?
Node.js, require.main === module
I have tested it, you could try it.@zhuoqinyue
JS:

TS is the same.

[justin-tse]

@zhuoqinyue, I am using ts-node to test my .ts file and it seems to be working well. However, I'm curious to know what kind of problems you are experiencing.

[zhuoqinyue]

It works a lot in JS, but doesn't work in TS.
ts-node throw a TSError

Your ts-node install in the global?

[zhuoqinyue]

The result tell me that ts-node doesn't have require @justin-tse

[justin-tse]

Yes, I think you should install @types/node, and try it.

[zhuoqinyue]

npm i @types/node --global

ts-node throw the same TSError again.

[zhuoqinyue]

But use npm i --save-dev @types/node, it works successfully.

[justin-tse]

It works a lot in JS, but doesn't work in TS. ts-node throw a TSError

Your ts-node install in the global?

@zhuoqinyue Good job! I think you misunderstand my meaning that I install ts-node in global but install @types/node in the devDependencies because it is only used in our local project. Your warning message tells you what to do.

[zhuoqinyue]

Could you tell me your config about @types/node, ts-node and typescript, such as json, path and version.
Because I failed again by using npm i --save-dev @types/node . @justin-tse

[justin-tse]

But use npm i --save-dev @types/node, it works successfully.

I see your last message which is a success. What's the problem now? The warning message?

The following is mine:

❯ tsc -v       
Version 4.8.4
❯ ts-node -v
v10.9.1
❯ npm list
hello-algo@ /Users/xf/src/justin-tse/open-source/hello-algo
└── @types/node@18.11.14 -> ./node_modules/_@types_node@18.11.14@@types/node

[zhuoqinyue]

Fine. I found my fault.
I should npm init -y in folder hello-algo firstly, and then npm i --save-dev @types/node.
Maybe we should add some gitignore rules for node_modules package.json?

[justin-tse]

OK, I think we don't push node_modules and package.json to this repository. These files are a little related to this project but are too big. You could give a comment before the line

// need to add the package @types/node contains type definitions for Node.js, npm i --save-dev @types/node
if (require.main === module)

[zhuoqinyue]

.gitignore make git to ignore some file or some folder change, as follows:

• before add rules node_modules/:
  
• after add rules node_modules/:
  

But git will detect the change of. gitgnore.

[zhuoqinyue]

OK, I think we don't push node_modules and package.json to this repository. These files are a little related to this project but are too big. You could give a comment before the line

// need to add the package @types/node contains type definitions for Node.js, npm i --save-dev @types/node
if (require.main === module)

I've updated it. @justin-tse

[justin-tse]

Thank you!@zhuoqinyue Clear codes! My suggestions to use explicit types or implicit types are:
It's generally a good practice to use explicit types for function parameters and return types, as well as for variables that can be of more than one type. However, for variables that can only have one type and where the type is clear from the value, implicit typing is often sufficient.

[zhuoqinyue]

OK, I've updated it

[justin-tse]

Thank you!@zhuoqinyue