Paperbase example Typography element uses href attribute improperly

[lookfirst]

• The issue is present in the latest release.
• I have searched the issues of this repository and believe that this is not a duplicate.

Current Behavior 😯

https://github.com/mui-org/material-ui/blob/master/docs/src/pages/premium-themes/paperbase/Header.js#L65

Typography has an href attribute, which is now invalid.

If you used typescript, you'd see this as an error and it would cause a nice build failure.

Expected Behavior 🤔

No error.

Steps to Reproduce 🕹

Use typescript.

Context 🔦

Trying to play with this awesome theme.

Your Environment 🌎

Tech	Version
Material-UI	master
TypeScript	3.5.3

[oliviertassinari]

This issue is part of a common theme, for instance: #16846, #16843 or #16487.

[lookfirst]

@oliviertassinari Thanks. I think the bigger issue is lack of use of Typescript in order to detect these sorts of issues at build time. I wonder at what point MUI gives in and goes full TS. I've personally been waiting years for the news. ;-) It sure would lower the number of issues filed as well as errors in your own codebase, this is a perfect example of it. It would also make maintaining all of those .d.ts files a thing of the past. POJS (plain old javascript) is dead.

[oliviertassinari]

Check #15984. We have hundreds of TypeScript demo that we run tests against. I think that it's a myth, a codebase written in TypeScript will only marginally improve our types, However, the psychological impact is high and interesting to exploit. The most important change so far has been the introduction of the TypeScript demos.

[lookfirst]

This bug wouldn't have happened if paperbase was in typescript. That alone is an improvement and not a myth.

I also see this project as a GREAT example for new developers on how to do things well. What you guys have accomplished over the years is awesome. In that sense, leading by example by using Typescript will only help increase its adoption and therefore (arguably) increase the quality of code that is out there that depends on this project. Much in the same way that paperbase is an example.

Moving to typescript also simplifies things... no more .d.ts files and only one set of demos to document. Less code is better.

[oliviertassinari]

The problem was fixed in #17213.

[lookfirst]

FANTASTIC