4 ms·

The code looks a bit messy to be honest, maybe it's just the variable naming. `const input$ = sources.DOM.select('.field').events('input')` Why not name it the

by XCSme 8y ago

The code looks a bit messy to be honest, maybe it's just the variable naming. `const input$ = sources.DOM.select('.field').events('input')` Why not name it the same as the DOM function `querySelector` ? `const name$ = input$.map(ev => ev.target.value).startWith('')` Wouldn't in this case `name$` be a boolean, but then `map` is called on a boolean. I just find the syntax very confusing.

typon 8y ago
What makes you guess that `name$` is a boolean?
- sritchie 8y ago
  I think the poster is assuming that .startWith(“) returns a Boolean, yeah?
  - coltonv 8y ago
    startWith, in this context of streams, means "let this value (in this case an empty string) be the first value the stream returns"
projectramo 8y ago
Perhaps you were thinking of “name?” Because there is nothing about “$name” that implies it’s a Boolean
jakelazaroff 8y ago
By convention, anything suffixed with $ is a stream. input$ is a stream of input events on all elements matching the selector ".field". The declaration for name$ says to take that stream of events and turn it into a stream of the value of those events, and to seed it with an empty string as the initial value. Reactive programming is a paradigm shift and definitely tough to wrap your head around at first. André Staltz (the creator of Cycle) has a good intro here: https://gist.github.com/staltz/868e7e9bc2a7b8c1f754 https://gist.github.com/staltz/868e7e9bc2a7b8c1f754
shados 8y ago
The conventions, naming, etc are not Cycle (or even JavaScript, in most case) specific. It's just straight out of the reactive programming ecosystem. I think Cycle uses XStream these days, assuming it didn't change again from last time I looked, and they renamed some stuff from the previous RxJS based implementation to be a bit friendlier, but even then the streams are not necessarily about DOM/html. CycleJS lets you do everything with streams, from managing http request or I/O and any other form of environment input. And yes, that includes DOM events, but it wouldn't make sense to name functions in a general API after a specific use case.
crucialfelix 8y ago
It's startWith not startsWith. I read it wrong myself too.

by XCSme 8y ago

typon 8y ago

What makes you guess that `name$` is a boolean?

sritchie 8y ago
I think the poster is assuming that .startWith(“) returns a Boolean, yeah?
- coltonv 8y ago
  startWith, in this context of streams, means "let this value (in this case an empty string) be the first value the stream returns"

projectramo 8y ago

Perhaps you were thinking of “name?” Because there is nothing about “$name” that implies it’s a Boolean

jakelazaroff 8y ago

By convention, anything suffixed with $ is a stream. input$ is a stream of input events on all elements matching the selector ".field". The declaration for name$ says to take that stream of events and turn it into a stream of the value of those events, and to seed it with an empty string as the initial value. Reactive programming is a paradigm shift and definitely tough to wrap your head around at first. André Staltz (the creator of Cycle) has a good intro here: https://gist.github.com/staltz/868e7e9bc2a7b8c1f754 https://gist.github.com/staltz/868e7e9bc2a7b8c1f754

shados 8y ago

The conventions, naming, etc are not Cycle (or even JavaScript, in most case) specific. It's just straight out of the reactive programming ecosystem. I think Cycle uses XStream these days, assuming it didn't change again from last time I looked, and they renamed some stuff from the previous RxJS based implementation to be a bit friendlier, but even then the streams are not necessarily about DOM/html. CycleJS lets you do everything with streams, from managing http request or I/O and any other form of environment input. And yes, that includes DOM events, but it wouldn't make sense to name functions in a general API after a specific use case.

crucialfelix 8y ago

It's startWith not startsWith. I read it wrong myself too.