Re: Programming to an Interface

On 2006-05-14 02:46:57 -0500, Laurent Bossavit <laurent@xxxxxxxxxxxxxxxxxxxx> said:

I think the point here is that one designs the interface first and then the implementation.

Whoever coined the phrase "Program to an interface" must have meant something else; otherwise they would have said "Program the interface first." From the start of this thread I've been wondering about the significance of phrasing it that way, program *to* an interface.

Any ideas ?

Laurent

I've always taken it to be a restatement of the Dependency Inversion Principle. When you call a method, call it on an interface or an abstract class, not on a concrete class.
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