Re: [Quickfix-developers] How to set custom/user-defined fields

[Caleb E. <ca...@bk...>]

On Mon, May 17, 2004 at 10:26:08AM -0500, Oren Miller wrote:

> Nope, that should be passed as a reference.  I made the change and 
> did a performance test and it actually doesn't make any difference, at 
> least when using an optimizer.  My guess is the optimizer is smart 
> enough to know that if you are passing in a const object, it might as 
> well pass it in as a reference anyway.  With the optimizer turned off 
> it there would be a significant difference.  In any case I'll check in 
> the change. 

	It depends where you do your testing I wager.  With gcc,
	std::string is reference counted, so leaving off the & should
	be more or less harmless.  On other platforms, though,
	std::string has copy semantics and this may help speed things
	up.

	Nto sure if you care about "ABI" compatibility, but this
	interface change will cause your new quickfix lib to be
	runtime-incompatible with older versions (since it will no
	longere provde the the setField method that takes a plain
	string).  You may want to provide *both* forms or bump at least
	the .so version number.

	Small change but potentially large impact.

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