prototype for operator proposal for review

Brendan Eich brendan at
Wed May 18 09:51:15 PDT 2011

On May 18, 2011, at 9:47 AM, Allen Wirfs-Brock wrote:

> I suspect that to most JS programmers the UML open triangle generalization arrow head is at least as relevant a precedent as any type theory uses.

I will take that bet. UML, ho ho! Maybe enterprise Java heads...

>  In other words,the relevancy of either isn't very high. 

Perhaps not, but Ruby's < is relevant to a good-sized cohort.

> One might argue that the prototype object is the more general and hence "smaller" object (the object on the right specializes the prototype by adding properties).

Yes, type narrowness is a dual of object population in JS, if you think of object with properties as an exemplar (prototype, even) of a latent structural type.

> In the end, these are just symbols  and JS programmer are just going to have to learn their meaning. Existing conventions, if they exist, and analogous do impact initial learnability but in the long run I don't know if it makes much a difference as long as they aren't prone to keyboarding hazards.

The precedents matter a bit, even if we try to create a new idiom. The problem is < not | (although doesn't that look too light in Helvetica on either side?).


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