On 9/4/2010 9:55 AM, OvermindDL1 wrote:
On Fri, Sep 3, 2010 at 5:46 PM, Joel de Guzman <joel@boost-consulting.com> wrote:
We once had outer. The outer solution looked like this:
for_each(_1, lambda [ push_back(_1, outer(_2)) ] )
How would that look like if you extend phoenix with your syntax?
It would be good to tackle this through practical use-cases and using plain C++ terms. Too much formality hurts my brain. If this use-case is too simplistic, then perhaps you can provide something more elaborate, yet still practical.
Actually that is pretty close to what I was describing, but imagine outer being like this to indicate how many levels up to go:
for_each(_1, lambda [ push_back(_1, outer<1>(_2)) ] )
Then simplify the syntax by doing something like outer<1,2>, which could then have a predefined value called _1_2 or so...
I like outer, guess it would be fully powerful if it could specify how many 'outer' levels to go out to with a template param like the above?
Yep. We had that too. There is also the possibility to write your own scoped place-holders like _1_2. I should reinstate them. I don't recall now why they were decommissioned. Perhaps because you can do what it does with local variables and lambda? I don't recall anymore. Regards, -- Joel de Guzman http://www.boostpro.com http://spirit.sf.net