7 ms·

What's funny about hooks?

recursive 5y ago
I know this is controversial, but I find them hard to understand. When I call `useState()`, what's the identity of the state that I'm using? What ties the state together between subsequent invocations of my component? For example, I know that strange things happen if you conditionally invoke `useState()`. People like to talk about "functional components", but hooks seem to live and breathe on mysterious side effects that I don't understand.
- jahewson 5y ago
  If only there was some way to discover how things worked... Some website where you could type “how react hooks work” and get dozens of articles and blog posts explaining it.
  - canadianfella 5y ago
    > If only there was That’s an annoying way to communicate.
  - mdoms 5y ago
    I understand how they work. That doesn't make the API any less insane.
  - recursive 5y ago
    You're probably aware of this, but those things already exist. Personally, I prefer to use things that make more sense, even if I read dozens of articles and blogs explaining them.
lucas_codes 5y ago
OP doesn't like them, so they're funny
mdoms 5y ago
They are apparently this panacea of elegant stateless code, but the developer is expected to know that multiple calls to useState must be made in the same order every time. Typically we associate APIs that are fragile to out-of-order calls with tightly coupled stateful systems. Not to mention the hideous use APIs. Thanks you, React, for this array which apparently contains a state and a setter?
- davnicwil 5y ago
  I think your first point gets to a tradeoff that isn't much discussed about hooks- they can be elegant and simple, but only assuming quite a bit of upfront knowledge about how they work. It's almost like taking the verbosity of class lifecycle methods, and 'pre compiling' it into a form which is terser, yes, but that now only a sufficiently informed reader can grok - the lifecycle is still there, it just has to be modelled by the reader instead of by the code. Sometimes this is a good tradeoff, but not always.
- grandpoobah 5y ago
  The developer isn't just "expected to know", because they'll get an error if they don't. React's debugger is really good at pointing out mistakes. As someone who started off thinking hooks were too "magic" to be taken seriously, such concerns are a thing of the past. If you just think of calls to useState as variable declarations, it makes zero sense that you'd ever want to call useState in a different order. this - let userName = 'bob'; let favouriteColour = 'purple'; is this let [ userName, setUserName ] = useState('bob)'; let [ favouriteColour , setFavouriteColour ] = useState('purple)'; Hooks enable you to reason about the state your component is in in a way that class components couldn't. Hooks felt extremely awkward to me at first, because it was forcing me to write code in ways that felt unnatural. Once I stopped fighting it, the benefits became apparent, and now the old way feels awkward. Hooks are to React what React was to jQuery.
- stnmtn 5y ago
  I've seen this a lot, when is an example of a time when you would want to call hooks out of order? I can't think of a single time where this would be a good thing to do

I know this is controversial, but I find them hard to understand. When I call `useState()`, what's the identity of the state that I'm using? What ties the state together between subsequent invocations of my component? For example, I know that strange things happen if you conditionally invoke `useState()`. People like to talk about "functional components", but hooks seem to live and breathe on mysterious side effects that I don't understand.

jahewson 5y ago
If only there was some way to discover how things worked... Some website where you could type “how react hooks work” and get dozens of articles and blog posts explaining it.
- canadianfella 5y ago
  > If only there was That’s an annoying way to communicate.
- mdoms 5y ago
  I understand how they work. That doesn't make the API any less insane.
- recursive 5y ago
  You're probably aware of this, but those things already exist. Personally, I prefer to use things that make more sense, even if I read dozens of articles and blogs explaining them.

lucas_codes 5y ago

OP doesn't like them, so they're funny

mdoms 5y ago

They are apparently this panacea of elegant stateless code, but the developer is expected to know that multiple calls to useState must be made in the same order every time. Typically we associate APIs that are fragile to out-of-order calls with tightly coupled stateful systems. Not to mention the hideous use APIs. Thanks you, React, for this array which apparently contains a state and a setter?

davnicwil 5y ago
I think your first point gets to a tradeoff that isn't much discussed about hooks- they can be elegant and simple, but only assuming quite a bit of upfront knowledge about how they work. It's almost like taking the verbosity of class lifecycle methods, and 'pre compiling' it into a form which is terser, yes, but that now only a sufficiently informed reader can grok - the lifecycle is still there, it just has to be modelled by the reader instead of by the code. Sometimes this is a good tradeoff, but not always.
grandpoobah 5y ago
The developer isn't just "expected to know", because they'll get an error if they don't. React's debugger is really good at pointing out mistakes. As someone who started off thinking hooks were too "magic" to be taken seriously, such concerns are a thing of the past. If you just think of calls to useState as variable declarations, it makes zero sense that you'd ever want to call useState in a different order. this - let userName = 'bob'; let favouriteColour = 'purple'; is this let [ userName, setUserName ] = useState('bob)'; let [ favouriteColour , setFavouriteColour ] = useState('purple)'; Hooks enable you to reason about the state your component is in in a way that class components couldn't. Hooks felt extremely awkward to me at first, because it was forcing me to write code in ways that felt unnatural. Once I stopped fighting it, the benefits became apparent, and now the old way feels awkward. Hooks are to React what React was to jQuery.
stnmtn 5y ago
I've seen this a lot, when is an example of a time when you would want to call hooks out of order? I can't think of a single time where this would be a good thing to do