Discovered by @amcasey while running TS on test262. ```ts export class IdentifierNameWithEscape { \u{78}: number; constructor() { this.\u{78} = 0; } doThing() { this.x = 42; } } export class PrivateIdentifierWithEscape { #\u{78}: number; constructor() { this.#\u{78} = 0; } doThing() { this.#x = 42; } } ``` Currently `IdentifierNameWithEscape` parses and type-checks correctly; however, `PrivateIdentifierWithEscape` does not even parse.