> I don't really understand [X]. Doesn't [Y] make your app difficult to reason and debug it?
It (passing mutable values around) does make it harder to understand the data-flow, yes.
But we programmers keep assuming our rules & protection & orderliness are helpful & necessary. And those patterns we opt in to keep getting codified, embraced. But along comes someone who breaks those rules, & it keeps turning out, a lot of the things we think we do to be orderly & safe & sensible are actually not that helpful at all, or have impeded really wonderful progress elsewhere.
I think of React. Until React came along, everyone doing web development knew, it was obviously correct, that we needed templating languages. We knew we needed content & code separate. We knew content was obviously a different beast than code & that content should have tools designed for content. As it turns out, mixing code & content actually works really well & that we had ruled out a wide space of possibilities that were really simple, powerful, & direct.
Relatedly, here, with shared-mutable-variables, I'd pitch that hopefully tools compensate for a lot. Hopefully it's possible to run the app & see who is modifying values, see who is being updated when values change. It's nice being able to have the code tell you, up front, easily, but also hopefully watching at runtime is possible, makes it easy to suss out what the connections & causalities are within a system.
It (passing mutable values around) does make it harder to understand the data-flow, yes.
But we programmers keep assuming our rules & protection & orderliness are helpful & necessary. And those patterns we opt in to keep getting codified, embraced. But along comes someone who breaks those rules, & it keeps turning out, a lot of the things we think we do to be orderly & safe & sensible are actually not that helpful at all, or have impeded really wonderful progress elsewhere.
I think of React. Until React came along, everyone doing web development knew, it was obviously correct, that we needed templating languages. We knew we needed content & code separate. We knew content was obviously a different beast than code & that content should have tools designed for content. As it turns out, mixing code & content actually works really well & that we had ruled out a wide space of possibilities that were really simple, powerful, & direct.
Relatedly, here, with shared-mutable-variables, I'd pitch that hopefully tools compensate for a lot. Hopefully it's possible to run the app & see who is modifying values, see who is being updated when values change. It's nice being able to have the code tell you, up front, easily, but also hopefully watching at runtime is possible, makes it easy to suss out what the connections & causalities are within a system.