better name for var_integer et.al.

[Andrew Cagney]

>>>  /* Unsigned Integer.  *VAR is an unsigned int.  The user can type 0
>>>     to mean "unlimited", which is stored in *VAR as UINT_MAX.  */
>>>  var_uinteger,
> 
> 
> Ada calls such numbers "Positive". var_positive might be a good name.

Or var_ordinal_number (vs cardinal number)?

>>>  /* Like var_uinteger but signed.  *VAR is an int.  The user can type 0
>>>     to mean "unlimited", which is stored in *VAR as INT_MAX.  */
>>>  var_integer,

Well, the "set backtrace limit 100" bug comes from a comparison between 
signed (frame->limit == -1) vs unsigned (backtrace_limit == 100) 
comparison which is from a var_uinteger.

Using var_integer "fixes" it but lets a user enter -100.

> I can't see any use for this semantics, but maybe it's due to my limited
> experience. I looked at the current code, and most if not all of them
> where just misuses of this kind. Some of them are really booleans (so I
> suspect var_zinteger would be better), or postive numbers (so
> var_positive would be better).
> 
> I not useful, I would consider just removing it.
> 
> 
>>>  /* ZeroableInteger.  *VAR is an int.  Like Unsigned Integer except
>>>     that zero really means zero.  */
>>>  var_zinteger,
> 
> 
> var_integer? (assuming we get rid of the non-zero signed integer)

Andrew