Two ExpressionStatements allowed on one line with no semicolon!

[conartist6]

🔎 Search Terms

ASI Automatic Semicolon Insertion

🕗 Version & Regression Information

unknown

⏯ Playground Link

No response

💻 Code

foo bar;

🙁 Actual behavior

no parse error

🙂 Expected behavior

parse error

Additional information about the issue

No response

[conartist6]

Other unexpected results are that this is perfectly valid code according to the TS parser

class Foo {
  static foo bar baz boom yuck what language is this (){
  }
}

[nmain]

This doesn't reproduce obviously in 6.0.2. Please fill out the entire template including a minimal, version numbers, etc.

[conartist6]

https://www.typescriptlang.org/play/?#code/MYGwhgzhAEBiD29oG8BQ1oQC5iwS2GgDNFoAjMAJ3LAC9zEBbaATwFdgBraAdwAtc0cADsA5mzCiAptDwwsfOdAAUASjQYAvqk1A

Looks like it repros on 6.0.2 to me

[nmain]

That example gives me 10 syntax errors in the playground. Look at all the squigglies:

[conartist6]

That example scrambles my brain. If it's just a matter of ignoring some spurious errors, surely that means that in this language omitting those extra symbols is a matter of semantics not syntax...?

[mkantor]

"Unexpected keyword or identifier" sounds like a syntax error to me. What do you mean by "ignoring some spurious errors"?

[snarbles2]

What are you expecting to happen that is not happening?

[conartist6]

I was expecting the runtime not to give concrete, definite, consistent (usable) meaning to undefined behavior.

The parse error feels more like a lint rule warning, and the ability to put two statements on one line feels like a fundamental ability of the Typescript language to me...

[conartist6]

It's probably only the fact that your parser isn't usually considered the definitive parser for typescript that makes this not really, really dangerous.

It's most likely the Prettier parser that is doing the heavy lifting on defining what syntax is valid Typescript

[nmain]

Duplicate of #44232.

[RyanCavanaugh]

There seems to be some kind of fundamental disconnect in interpretation here, not a bug.

The parse error feels more like a lint rule warning, and the ability to put two statements on one line feels like a fundamental ability of the Typescript language to me

We can't help that you don't like the vibes of the error. I don't understand how a language would remove the ability of you to write invalid syntax, except to define all possible sequences of characters as valid programs, which doesn't seem to be what you're asking for either.