Playground: incomplete hex escape in string triggers an infinite loop

[k4b7]

Typing the following code into the playground will trigger an infinite loop which stalls the browser:

let a = "\x

The same happens if you type an empty string first and then add the \x inside of it. I tried reproducing this with bsc.exe but it exits with an appropriate syntax error in both situations so this appears to be playground specific. I paused the debugger and saw that it's trying to get the char code of some string at a very large index.

[ryyppy]

that's probably something for @bobzhang Maybe that's an issue with the jsoo'ed output?

[fhammerschmidt]

not reproducible anymore