AMDG On 03/31/2011 11:27 AM, Robert Jones wrote:

On Thu, Mar 31, 2011 at 4:47 PM, Steven Watanabewrote:

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On 03/31/2011 08:29 AM, Robert Jones wrote:

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From Bjorn Karlsson's book, P297...

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int i; int value = 12; var(i) = ( if_then_else_return( _1>=10, constant(10),_1) )(value);

Why does the assignment LHS need to be wrapped in var()?

Because operator= must be a member function.

Nope, still not getting it! Stop me when I err...

if_then_else_return(...) defines a unary functor it_then_else_return(...)( value) evaluates that functor, and returns what?

Some type of integer I think?

Yes.

So doesn't the assignment simply perform assignment of an integer, by copy? And that doesn't need operator= to a member of anything?

Oh, I see. As written, the code doesn't make much sense, so my mind automatically translated it into (var(i) = if_then_else_return( _1>=10, constant(10),_1) )(value); In Christ, Steven Watanabe