This commit implements parsing for `yield *expr`, and the multiple
ways something can or can't be parsed like that.
Also makes yield-from a TODO in the bytecode generator.
Behold, the glory of javascript syntax:
```js
// 'yield' = expression in generators.
function* foo() {
yield
*bar; // <- Syntax error here, expression can't start with *
}
// 'yield' = identifier anywhere else.
function foo() {
yield
*bar; // Perfectly fine, this is just `yield * bar`
}
```
This patch adds an "argument index" field to Identifier AST nodes.
If the Identifier refers to a function parameter in the currently
open function scope, we stash the index of the parameter here.
This will allow us to implement much faster direct access to function
argument variables.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)
Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.
We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.
