microsoft / microsoft/TypeScript

The parsing problem of the compiler under specific syntax combinations

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#61,975 2 comments 0 reactions 1 assignee View on GitHub

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Since Aug 6, 2025.

Bug Domain: Parser Help Wanted
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Description

### 🔎 Search Terms

The parsing problem of the compiler under specific syntax combinations

### 🕗 Version & Regression Information

- This is the behavior in every version I tried

### ⏯ Playground Link

https://www.typescriptlang.org/play/?ts=5.8.3#code/MYGwhgzhAEAKYDsAuAnAlgUwgHgIID5poBvAKCKOAHsEJUBXYJKlACgAcUNg0IMAuaLgCUJchQlIAFrwB0nbrwzQAvNAU8+4ogF9t6rpoFDSe0gDN6CJmhrQI7MChRUA7q2GCARlSogMiGIS1LRI9lReXhgAJt6+-oFqDBgA3KT6XEj0KAhEAERgXsB50NjQrBARUdHQAPzQCBiucIiomDh06AgA5visBXmigo3N8MjoWNidaD19eV6D0MLyhkppZumW1ki2uQ5OLq4AjB6C0z1BFCF04ZExcX4BuUko9KnpEpnZueWVdzX1EYtcbtKZtWb9MCLYZNYFtSbnXr9BaiZYaNamdIWKw2Oz7ZxuABMp2gPkegTIwRoNz+1QeCWe0GSaQyGCyOXyhWKpV+VRidXKQLG8I64KRA2EQwasOFE1FXXFKKWK0UfHWpCAA

### 💻 Code

```ts
class Pantries {
constructor(precise: A) {
this.precise = precise
}
precise: A
}

function sparrow(): boolean {
const sobbed: boolean = true;

return "abc" < (sobbed ? new Pantries("a") : new Pantries("b") ).precise;
}

function sparrow1(): string {
const sobbed: boolean = true;

return (sobbed ? new Pantries("a") : new Pantries("b") ).precise;
}

function sparrow2(): boolean {
const sobbed: boolean = true;

return "abc" < (sobbed ? (new Pantries("a")) : new Pantries("b") ).precise;
}

```

### 🙁 Actual behavior

There was a problem when parsing the sparrow method, while the other methods worked fine.

### 🙂 Expected behavior

There will be no error reports or clear prompts

### Additional information about the issue

_No response_

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