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[Denis Koroskin]

On Fri, 10 Oct 2008 19:37:28 +0400, Andrei Alexandrescu  
<SeeWebsiteForEmail at erdani.org> wrote:

> Denis Koroskin wrote:
>> On Fri, 10 Oct 2008 19:19:45 +0400, Sergey Gromov  
>> <snake.scaly at gmail.com> wrote:
>>
>>> Fri, 10 Oct 2008 19:10:19 +0400,
>>> Denis Koroskin wrote:
>>>> On Fri, 10 Oct 2008 18:33:43 +0400, Andrei Alexandrescu
>>>> <SeeWebsiteForEmail at erdani.org> wrote:
>>>>
>>>> > Sergey Gromov wrote:
>>>> >> I'd also like
>>>> >>   "foo" ~ text ~ "bar"
>>>> >> to become something like
>>>> >>   (new Array!(char)) ~= "foo" ~= text ~= "bar"
>>>> >> that is what Java does to string concatenation.  Sugar doesn't  
>>>> seem to
>>>> >> couple well with a purely library type.
>>>>
>>>> I doubt that. Java strings are immutable, their length can't be  
>>>> changed
>>>> either (i.e. they are a direct analog of a proposed  
>>>> invariant(char)[]).
>>>> Concatanating Java strings don't turn them into array, and it is dead
>>>> slow. Every sane person uses StringBuilder instead.
>>>
>>> Java compiler substitutes
>>>
>>> "foo" + text + "bar"
>>>
>>> with
>>>
>>> new StringBuilder().append("foo").append(text).append("bar").toString()
>>>
>>> all by itself because both String and StringBuilder are built-in
>>> classes.
>>  Yes, you are right. From The Java Language Specification, 3rd edition:
>>
>>> To increase the performance of repeated string concatenation,
>>> a Java compiler may use the StringBuffer class or a similar technique
>>> to reduce the number of intermediate String objects that are created
>>> by evaluation of an expression.
>
> But that doesn't require StringBuffer to be part of the language. With  
> literals, the compiler can do whatever magic it wants.
>
> Andrei

Of course.

C# solution needs consideration, too, I believe: it substitutes "foo" ~  
text ~ "bar" with String.Concat("foo", text, "bar");