Re: [boost] Variadic append for std::string

Subject: Re: [boost] Variadic append for std::string
From: Christof Donat (cd_at_[hidden])
Date: 2017-01-13 10:30:09

Hi,

Am 12.01.2017 20:05, schrieb Olaf van der Spek:
> On Wed, Jan 11, 2017 at 5:45 PM, Christof Donat <cd_at_[hidden]> wrote:
>> Basically the Idea of that kind of interface should work as well for a
>> high performance solution. Let's start with this syntax:
>> 
>> auto myString = (cat() + "Hello"s + " "s + "World! "s + 42).str();
>> 
> 
> I like fmt's syntax much more:
> 
> string s = fmt::format("The answer is {}", 42);
> 
> 
> http://fmtlib.net/latest/index.html
> 
> I really don't get why we should bother with the (cat(...)).str() bit.

Format will have to parse the format string at runtime and then chose 
dynamically the function to stringify the number. The cat() aproach can 
be implemented to do that choice at compiletime. So no string parsing 
and not dynamic choice of formating functions. We were talking about 
performance in this chapter, weren't we?

Christof