Sometime if our tsconfig.json looks like this;
{ "compilerOptions": { "target": "es5", "module": "commonjs", "outDir": "dist" } }
We can get all kinds of type autocomplete in VSCode such as :
Array.isArray([])
But we don‘t have:
Array.from(document.queryElmentsById(‘button‘))
it shows red underline.
This is because we are just targeting "es5":
"target": "es5",
To solve the issues, we can use:
{ "compilerOptions": { "target": "es5", "lib": ["es6"], "module": "commonjs", "outDir": "dist" } }
But now, we have another problem for "docuemnt".
to fix this:
{ "compilerOptions": { "target": "es5", "lib": ["es6", "dom"], "module": "commonjs", "outDir": "dist" } }
[Typescript] Understanding “lib” and ES libraries
原文：https://www.cnblogs.com/Answer1215/p/13770573.html