Re: From dynamic to static

[Chris Marrin <chris@...>]

David Given wrote:
> ...
> But the really cunning bit is that this applies to objects too. I can't 
> remember the syntax, so I'll switch to Lua-esque pseudocode. This:
>
> o:method1()
>
> ...tells the compiler that o must be an object that implements method1. This 
> means that you can pass in *any object* that happens to implement method1 --- 
> it'll work, and be statically typed. Using his example, you could implement 
> Cat, Dog and Bob has three seperate classes, and provided they all 
> implemented the 'speak()' method, this function:

But this cannot be known at compile time in Lua (or any other 
dynamically typed language that I know of). At compile time o may not 
have a method1 function. But it hopefully will by the time it gets called.

--
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"As a general rule,don't solve puzzles that open portals to Hell"'