Char.length

[Jane Doe via Digitalmars-d]

On Thursday, 10 July 2014 at 17:11:14 UTC, John Colvin wrote:
> On Thursday, 10 July 2014 at 17:01:45 UTC, Jane Doe wrote:
>> One thing that bothers me quite a bit is that char's do not 
>> have length. This makes it difficult in templates that can 
>> take either strings or chars.
>>
>> While one can write a template that returns the length of a 
>> string or char, I would imagine that this could be implemented 
>> in the compiler more efficiently?
>>
>>    char.length always returns 1.
>>
>> Similarly, it would be nice to be able to use [] on chars.
>>
>>    char[x] returns char.
>>
>> Example:
>>
>>    auto last(T)(T s) { return s[s.length-1]; }
>>
>>    void main()
>>    {
>> 	writeln(last("asdf"));
>> 	writeln(last('c'));       // fails!! But surely this should 
>> work!
>>    }
>>
>>
>>
>> http://dpaste.dzfl.pl/cba5a635d08e
>>
>>    Error: s must be an array or pointer type, not char
>>    Error: no property 'length' for type 'char'
>>
>> Basically, I see no reason why char's can't be more confluent 
>> with strings, at least on the surface. I would reduce code 
>> bloat/specialization for no real reason.
>>
>> If the compile knows a type is a char then char.length = 1 and 
>> char[x] = char. Shouldn't be hard or cause any problems?
>
> It looks nice on the surface but it quite quickly unravels.
>
> string and char are very different types: one is a single-byte 
> value type, the other is a 16 byte (on x64) structure 
> representing an arbitrary length window on to arbitrary memory.
>
> The situations where they are interchangeable in code are the 
> exceptions, not the rule.


This is simply wrong. There are man types with functionality of 
length. One can create a class Char that has lenght. Arrays have 
length.