问题
E.g. @import url("~./foobar");
Saw it here, not sure if it's some package specific thing or if it's actual CSS syntax.
回答1:
The CSS @import path <url> is usually relative to the current working directory.
So using the prefix ~ at the start of the path tells the Webpack loader to resolve the import "like a module" from a node module path.
What that means is that if you have a node module called normalize installed, and you need to import a file from within it named /normalize.css, you can do that with:
@import "~normalize/normalize.css";
In your linked example, inside font-loader/example/test.js there is an import of a module called font-boon.
var boon = require('./font-boon');
Inside of font-loader/example/test.css the font-boon module is @imported so that it is available in text.css.
@import url("~./font-boon");
来源：https://stackoverflow.com/questions/39535760/what-does-a-tilde-in-a-css-url-do