What is the best declaration type for a string like parameter?

[Puming via Digitalmars-d-learn]

On Thursday, 28 January 2016 at 15:03:38 UTC, sigod wrote:
> On Thursday, 28 January 2016 at 13:36:46 UTC, Puming wrote:
>> [...]
>
> `in char[]` is short for `scope const char[]` or `scope 
> const(char[])`.
>
> See http://dlang.org/spec/function.html#parameters
>
> It depends on the situation. If possible I would use `in` 
> modifier. If not then just `const`.
>
>> [...]
>
> Please, don't define such aliases. I'm sure a lot of developers 
> will find it confusing. As I do.
>
> `const(char)[]` or `in char[]` is perfectly understandable as 
> soon as you know what it means.
>
> Also, read this: http://dlang.org/spec/const3.html

Thanks. Now I get it.

Yes it is understandable now, but as a newbie the question "Why 
my function that accepts a string does not work with lines in 
file?" will pop.