Re: [boost] Phoenix review

Subject: Re: [boost] Phoenix review
From: Giovanni Piero Deretta (gpderetta_at_[hidden])
Date: 2008-09-25 08:54:55

On Wed, Sep 24, 2008 at 10:00 PM, Doug Gregor <dgregor_at_[hidden]> wrote:
<snip>
> Is "lambda" equivalent to BLL's "unlambda" or "protect"?

as far as I can tell no, because boost::lambda::protect(f) is
basically the identity, except that it changes the type of 'f', hiding
its 'lambdiness'.

OTOH phoenix::lambda[f] returns a stub that in turns returns 'f' (I
didn't check if the type of 'f' is changed). The phoenix machinery
makes sure that when used as a nested lambda expression, lambda[]
actually work more or less like protect. The abstraction break if you
use lambda[]  as top level.

For more on this topic, see my comments about phoenix on another mail.

-- 
gpd