In theory purity unlocks optimizing potential, but in practice I don't think what you're saying holds true. Mutating a value is almost always cheaper than allo

In theory purity unlocks optimizing potential, but in practice I don't think what you're saying holds true. Mutating a value is almost always cheaper than allocating a new version of that value and collecting the old one. I think you're vastly understating the "you can usually" and overstating the "much less readable and maintainable".