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Awaiting More FeedbackThis means we'd like to hear from more people who would be helped by this featureThis means we'd like to hear from more people who would be helped by this featureSuggestionAn idea for TypeScriptAn idea for TypeScript
Description
According to the PR of #32221 , to prevent such problem like:
(function () {
function cleanup() {
console.log(A); // throw error
}
cleanup();
const A = 1;
}());
this snippet will compile into:
(function () {
function cleanup() {
console.log(A); // log undefined
}
cleanup();
var A = 1;
}());
Error in the first snippet will be ignored, and cause TDZ error. Can tsc
support TDZ error enabled option like babel-plugin-transform-block-scoping ? It will notify peoples who write such pattern to prevent further weird problems.
Checklist
My suggestion meets these guidelines:
- This wouldn't be a breaking change in existing TypeScript/JavaScript code
- This wouldn't change the runtime behavior of existing JavaScript code
- This could be implemented without emitting different JS based on the types of the expressions
- This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
- This feature would agree with the rest of TypeScript's Design Goals.
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Awaiting More FeedbackThis means we'd like to hear from more people who would be helped by this featureThis means we'd like to hear from more people who would be helped by this featureSuggestionAn idea for TypeScriptAn idea for TypeScript