React Flow Tutorial ( Static Type Checking Props, State and set Default Props )

Static Type Checking with Flow in ReactJS, Installation , Setup, Prop Type guards for components and Type Checking for State.

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[nemethmik]

The real gem of Flow is Exact (Props/State) Object definitions to prevent the absolutely most dreaded JS errors: typos. Something like this:
type AppType = {|
burgerName?: string,
basePrice?: number
|}

[itstrending]

Cannot build a typed interface for this module. You should annotate the exports of this module with types. Missing type
annotation at function return:

[avikunj]

I created react project with typescript template and later on added flow. I am getting errors in "and .
The error is "Unexpected end of input, expected the token". I tried to ignore the node_modules in .flowconfig but no luck and still getting same error.
Please assist if you can, it would be helpful.

[radosawguchowski]

Hi Techsith, I learning for front-end dev, and sometimes I watching u videos, I think they are good advice.
Regards.
Ps. "I have Created this project by using Create-React-App" is funny :D

[gabrielfono]

when I use <{}>, I have an error cuz the browser says" it is only supported by typeScript"
what should I do??

[samrathchauhan]

sad for me I don't see a link for the series. what a bad day 😭

[milanregmi]

have you ever used flow with styled-components? I am having very difficult time with styled-components.

[rohanshastri]

I am getting yarn not found. Do I have to install yarn explicitly or is it bundled when I have installed npm

[firewatermoonsun]

Why funcComp component doesn't start with capital letter?

[IlanPerez]

Do you have a flow video explaining interfaces...

[Gentarozzo]

Hey man... can we use file with flow types in the production build? Should we compile It in JS before? I think that's important to talk about

[arohsunday]

great tutorial. Please i notice that running : "yarn run flow" is very slow. is there any workaround to make it fast

[djslimcodes]

at 15:59 I need to start the name of functional component with the capital letter, otherwise React won't find it ( at least in Webstorm), any reasons for that?

[kirankamath]

Hi sir, i am getting error as (Type alias can only be used as typescript) while using testprops afyter component, what is the solution

[ParsiMusik]

don't get what I'm doing wrong ...

type myType = {
somethingArray: array,
}

export default class myClass<myType> {
somethingArray = []
}


error:

[eslint] Type aliases require valid Flow declaration.
[eslint] 'myType' is defined but never used. (no-unused-vars)
[eslint] 'myType' is already declared in the upper scope. (no-shadow)

[hellonehha]

When we use type in VS it gives the error that type is only supported for .ts file. how you fixed this issue?

[djslimcodes]

at 6:19 where that syntax for excluding files comes from, because it's not js syntax?

[titivermeesch]

For the latest version you have to ignore the following, just a tip : .*/src/serviceWorker\.js