When TCL gets a string that starts with a `0` as its return value, it'll treat it as an octal number and will return the decimal value of the octal number. Is there a way to circumvent it and force `expr` to address the value as a string?

I encounter this problem because I have a line:

```
set val [expr {( $obj == "" ) ? "" : [$obj data]}]

```

And one the results of the `[$obj data]` operation is a binary string starting with 0, and the `expr` turns it into another number. Is there a way to fix this without turning the `expr` into an `if`?