Poor support for TypeScript not-null assertions

Bug Report

Current Behavior TypeScript’s postfix ! not-null assertion isn’t supported in various commonly used scenarios, such as a! *= 1; and a! / 10

Input Code

function doSomething(a: number | null) {

  // SyntaxError: src/test.ts: Unexpected token =
  a! *= 1;

  // SyntaxError: src/test.ts: Unterminated regular expression
  return a! / 2;

}

Expected behavior/code No error

Babel Configuration (.babelrc, package.json, cli command)

{
	"plugins": [
		"@babel/plugin-transform-typescript"
	]
}

Environment

• Babel version(s): v7.0.0-beta.47
• Node/npm version: Node 10.1.0 / npm 6
• OS: macOS 10.13.4
• Monorepo ?
• How you are using Babel: cli

[nicolo-ribaudo]

a! = 2 has been fixed by https://github.com/babel/babel/pull/7888

[CoskunSunali]

@existentialism babylon@7.0.0-beta.47, let me know if you need any configuration files from my project.

Unexpected token, expected ";" (369:44)

Line 369 is: const x = document.getElementById('foo')!;

Char 44 is ! with 4 spaces in front of the const keyword.