Re: [Boost-users] Pattern-matching by metaprogramming - possible?

From: Zeljko Vrba (zvrba_at_[hidden])
Date: 2007-10-18 05:07:40

On Thu, Oct 18, 2007 at 09:04:39AM +0200, Ovanes Markarian wrote:
>
> Hello Zeljko,
> 
> may be another approach? Why not using a template method and static concepts
> inside a function, which ensure that a parameter is of correct type?
> 
Hmm, I didn't quite get you.  But I want to match both on *type* and *value*
as shown in this rule:

>
> >         | (Insn "addq", Reg "%rsp") -> (* do something *)
>

The type here is (Insn, Reg) [particular types of larger variants];
each component is also matched on the particular value ("addq" and
"%rsp" strings).

>
> >         | (_, Imm x) -> (* any 1st item; the 2nd must be Imm type, and
> >                 the x variable is bound to the value carried by the 2nd
>

The type here is doesn't matter and (Imm x) - this is a match only
on type where the variable x gets bound to the value carried by
the variant type.