2 let ok = "{{everything fine}}";
3 let bad = "\{it is wrong\}";
4 //~^ ERROR unknown character escape: `{`
5 //~| HELP if used in a formatting string, curly braces are escaped with `{{` and `}}`
6 //~| ERROR unknown character escape: `}`
7 //~| HELP if used in a formatting string, curly braces are escaped with `{{` and `}}`