[m-rev.] for review: generalise the representation of integers in the term module

[Julien Fischer]

Hi Peter,

On Sat, 22 Apr 2017, Peter Wang wrote:

>> diff --git a/library/lexer.m b/library/lexer.m
>> index 1cb2427..822f2de 100644
>> --- a/library/lexer.m
>> +++ b/library/lexer.m
>> @@ -30,7 +30,7 @@
>>   :- type token
>>       --->    name(string)
>>       ;       variable(string)
>> -    ;       integer(int)
>> +    ;       integer(integer_base, int)
>>
>>       ;       big_integer(integer_base, integer)
>>               % An integer that is too big for `int'.
>
> Will integer and big_integer be combined when the integer literal
> syntax is extended?

They will be combined.  (I'm actually bootchecking the
change that combines them as I write this.)

>> diff --git a/library/term.m b/library/term.m
>> index feab9cf..fa1b6e3 100644
>> --- a/library/term.m
>> +++ b/library/term.m
>
>> @@ -762,6 +788,31 @@ var_id(var(VarNum)) = VarNum.
>>
>>   %---------------------------------------------------------------------------%
>>
>> +term_to_int(Term, Int) :-
>> +    Term = functor(Const, [], _),
>> +    Const = integer(_, Integer, signed, size_word),
>> +    integer.to_int(Integer, Int).
>> +
>> +term_to_uint(Term, UInt) :-
>> +    Term = functor(Const, [], _),
>> +    Const = integer(_, Integer, unsigned, size_word),
>> +    integer.to_uint(Integer, UInt).
>
> Write _Base and _Context.

Done.

>> +
>> +term_to_decimal_int(Term, Int) :-
>> +    Term = functor(Const, [], _),
>> +    Const = integer(base_10, Integer, signed, size_word),
>> +    integer.to_int(Integer, Int).
>
> The name is a bit confusing as result does not have any inherent base,
> obviously.  Would decimal_term_to_int be better?

Ok, I will change the name.

>> +
>> +decimal_int_to_term(Int, Context) = Term :-
>> +    Const = integer(base_10, integer(Int), signed, size_word),
>> +    Term = functor(Const, [], Context).
>
> int_to_decimal_term?

Ditto.

>> +
>> +decimal_uint_to_term(UInt, Context) = Term :-
>> +    Const = integer(base_10, integer.from_uint(UInt), unsigned, size_word),
>> +    Term = functor(Const, [], Context).
>> +
>
> Likewise.

Ditto.

>> diff --git a/library/term_conversion.m b/library/term_conversion.m
>> index 9464c69..7082d17 100644
>> --- a/library/term_conversion.m
>> +++ b/library/term_conversion.m
>> @@ -209,9 +210,15 @@ term_to_univ_special_case(ModuleName, TypeCtorName, TypeArgs, Term,
>>               type_to_univ(String, Univ)
>>           ;
>>               TypeCtorName = "int",
>> -            Functor = integer(Int),
>> +            Functor = integer(_, Integer, signed, size_word),
>> +            integer.to_int(Integer, Int),
>>               type_to_univ(Int, Univ)
>>           ;
>> +            TypeCtorName = "uint",
>> +            Functor = integer(_, Integer, unsigned, size_word),
>> +            integer.to_uint(Integer, UInt),
>> +            type_to_univ(UInt, Univ)
>
> Write _Base.

Done.

>> diff --git a/library/term_io.m b/library/term_io.m
>> index 8139f74..226641e 100644
>> --- a/library/term_io.m
>> +++ b/library/term_io.m
>> @@ -565,7 +565,7 @@ write_list_tail(OutStream, Ops, Term, !VarSet, !N, !IO) :-
>>       %
>>   :- pred starts_with_digit(term(T)::in) is semidet.
>>
>> -starts_with_digit(functor(integer(_), _, _)).
>> +starts_with_digit(functor(integer(_, _, _, _), _, _)).
>>   starts_with_digit(functor(float(_), _, _)).
>>   starts_with_digit(functor(atom(Op), Args, _)) :-
>>       (
>> @@ -606,10 +606,8 @@ write_constant(OutStream, Const, !IO) :-
>>
>>   write_constant(OutStream, Const, NextToGraphicToken, !IO) :-
>>       (
>> -        Const = term.integer(I),
>> -        io.write_int(OutStream, I, !IO)
>> -    ;
>> -        Const = term.big_integer(Base, I),
>> +        Const = term.integer(Base, I, _Signedness, _Size),
>> +        % XXX UINT hand signedness and size.
>
> handle

Fixed.

> The rest looks fine.

Thanks for the review.

Julien.