3 ms·

It's not about changing everything, it's about being able to make abstractions that aren't second class citizens. By giving this power, you also increase the c

by sbov 10y ago

It's not about changing everything, it's about being able to make abstractions that aren't second class citizens. By giving this power, you also increase the consistency of the language.

stcredzero 10y ago
By giving this power, you also increase the consistency of the language. Maybe. That's like the apocryphal story about the student asking a question if a particular proof step is really obvious, so the professor goes across the hall, derives stuff on the other blackboard for the next 30 minutes, then comes back into the lecture hall saying, "Yes, it's obvious." Maybe you increase the consistency of the language from one point of view, but what happens from the perspective of each individual project? What if this leads to projects where templates have been used to create 3 different template based "little languages" to make X, Y, and Z easier? You had 3 problems, but now you have 6. The oft written reply to that in these debates, is to limit the power of the template system -- but is that a robust goal under the group dynamics of the language community? I think not. One subliminal goal in the design of Go seems to be about privileging certain conventions to avoid a babel of roll-your-own conventions in large projects. This is all across the language and even in the toolchain.
- catnaroek 10y ago
  The problem with templates is that they're ad-hoc: they can be specialized, and they're only checked at instantiation time. C++'s type level is literally a dynamic language, and template errors are literally stack traces, only made worse by backtracking, due to the deepest unification rule and SFINAE. But bona fide parametric polymorphism doesn't have this problem. ML's design is a constructive proof that you can have a reasonable degree of abstraction without compromising usability.

3 ms·

It's not about changing everything, it's about being able to make abstractions that aren't second class citizens. By giving this power, you also increase the c

by sbov 10y ago

It's not about changing everything, it's about being able to make abstractions that aren't second class citizens. By giving this power, you also increase the consistency of the language.

stcredzero 10y ago
By giving this power, you also increase the consistency of the language. Maybe. That's like the apocryphal story about the student asking a question if a particular proof step is really obvious, so the professor goes across the hall, derives stuff on the other blackboard for the next 30 minutes, then comes back into the lecture hall saying, "Yes, it's obvious." Maybe you increase the consistency of the language from one point of view, but what happens from the perspective of each individual project? What if this leads to projects where templates have been used to create 3 different template based "little languages" to make X, Y, and Z easier? You had 3 problems, but now you have 6. The oft written reply to that in these debates, is to limit the power of the template system -- but is that a robust goal under the group dynamics of the language community? I think not. One subliminal goal in the design of Go seems to be about privileging certain conventions to avoid a babel of roll-your-own conventions in large projects. This is all across the language and even in the toolchain.
- catnaroek 10y ago
  The problem with templates is that they're ad-hoc: they can be specialized, and they're only checked at instantiation time. C++'s type level is literally a dynamic language, and template errors are literally stack traces, only made worse by backtracking, due to the deepest unification rule and SFINAE. But bona fide parametric polymorphism doesn't have this problem. ML's design is a constructive proof that you can have a reasonable degree of abstraction without compromising usability.