Proto for Boost mailing list page: [proto] proto::expr vs. proto::basic_expr

Subject: [proto] proto::expr vs. proto::basic_expr
From: Thomas Heller (thom.heller_at_[hidden])
Date: 2011-05-15 10:19:28

Hi,

Today I experimented a little bit with phoenix and proto.
My goal was to decrease the compile time of phoenix. When I started the 
development of phoenix, Eric advised me to use proto::basic_expr to reduce 
compile times.
Which makes sense giving the argumentation that on instatiating the expression 
node, basic_expr has a lot less functions etc. thus the compiler needs to 
instantiate less. So much for the theory.
In practice this, sadly is not the case. Today I made sure that phoenix uses 
basic_expr exclusively (did not commit the changes).

The result of this adventure was that compile times stayed the same. I was a 
little bit disappointed by this result.

Does anybody have an explanation for this?

Regards,
Thomas