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Evaluate compile-time constants

See original GitHub issue

TypeScript Version: 3.5.0-dev.20190511

Search Terms:

compile-time operations numerical constants

Code

main.ts

const TWO: 2 = 1 + 1;

Expected behavior:

Transpiles without error

Actual behavior:

$> tsc main.ts

main.ts:1:7 - error TS2322: Type ‘number’ is not assignable to type ‘2’.

Playground Link:

https://www.typescriptlang.org/play/#src=const TWO%3A 2 %3D 1 %2B 1%3B

Related Issues:

Issue Analytics

State:
Created 4 years ago
Comments:9 (5 by maintainers)

Top GitHub Comments

2reactions

Morglodcommented, Apr 2, 2021

https://github.com/Morglod/tsts

Currently working on comptime transformer

const numbers = [ 1, 2, 3, 4, 5, 6, 7, 8 ];
const result = comptime(() => {
    return numbers.reduce((total, x) => sum(total, x), 0);
});

const result = (() => { return (36); })();

0reactions

n0izn0izcommented, May 27, 2019

Even if MESSAGE_BYTES is a constant used in another part of the program?

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