Single exclamation mark leads to parser issue

```golang
func hello() string {
	return "hello"
}

func buildGreeting(p string) string {
	return hello() + " " + p
}
exc := "!"
greeting := buildGreeting("world" + exc)

print(greeting) // Prints "Hello World" to the console.
```

```
panic: unknown expression type 27 "
        " at row 8, column 11
```