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Are nat-dependent types possible?

See original GitHub issue

I am writing a matrix type and a matrix multiplication function. What I would like is to have types Matrix<n,m> indexed by positive integers n, m so that the multiplication has signature

Matrix<n,m> -> Matrix<m,p> -> Matrix<n,p>

(so trying to multiply matrices of incompatible dimensions is a type error).

I have seen an implementation of this in F# (https://www.youtube.com/watch?v=3zdlQ_HjKl4 ) but the approach is quite hacky… Is it possible to do this neatly with F#+?

Issue Analytics

State:
Created 4 years ago
Comments:27 (22 by maintainers)

Top GitHub Comments

3reactions

gustycommented, Oct 14, 2019

That’s great. To me the tuple version looks much better and flexible.

3reactions

cannorincommented, Aug 10, 2019

I think I can help with this (once #174 is done)

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