mirror of
https://github.com/vercel-labs/scriptc.git
synced 2026-10-31 07:23:06 +08:00
Chris Tate
06b03f06a9
* Compose class references across unions and collections - Compare class, function and native references held in differently represented unions with `===`, `!==` and `Object.is` while preserving subclass identity, and refuse comparisons that a structural union arm leaves undecidable - Keep subclass values intact through base-typed array and Set insertion spreads, `concat`, and inferred class-predicate `filter`/`find`/`findLast`, and allow checked class refinement of captured optional values with several class arms - Split the sanitized compiler self-rebuild CI job at the IR boundary, after giving sort helpers distinct IR nodes so serialized and in-memory IR emit the same LLVM * Keep compact comparisons for plain union arms - Compare a plain operand with a union that already holds its type through the existing inline union comparison, preserving established parameter representations - Update the coverage expectation for the accepted class refinement
35 lines
1012 B
TypeScript
35 lines
1012 B
TypeScript
// Structural refinements still need a named fence for multi-value storage.
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// The class refinement below is accepted through a checked identity-preserving view.
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type Item = { rect?: { width: number } };
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function hasRect(item: Item | string): item is Item & { rect: { width: number } } {
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return typeof item !== "string" && item.rect !== undefined;
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}
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function recordWidths(items: (Item | string)[]): void {
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for (const item of items) {
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if (hasRect(item)) console.log(item.rect.width);
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}
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}
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class Animal {
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name: string;
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constructor(name: string) { this.name = name; }
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}
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class Dog extends Animal {
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bark(): string { return this.name; }
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}
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function isDog(animal: Animal | string): animal is Dog {
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return typeof animal !== "string" && animal instanceof Dog;
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}
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function classNames(animals: (Animal | string)[]): void {
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for (const animal of animals) {
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if (isDog(animal)) console.log(animal.bark());
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}
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}
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recordWidths([{ rect: { width: 1 } }, "plain"]);
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classNames([new Dog("dog"), "plain"]);
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