radmen · March 6, 2018 08:34 · Mar 5, 2018 · Mar 5, 2018
diff --git a/gistfile1.txt → gistfile1.md b/gistfile1.txt → gistfile1.md
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+# The task
+
+1. get something from a remote site (`loadPage()`)
+1. find specific element (`findElement()`)
+1. grab and parse contents as JSON (`extractJson()`)
+
+# stage 1
+
+Easy way: grab page and return result
+
+```js
+const task = async url => {
+  // loadPage :: String -> Promise Page
+  const page = await loadPage(url)
+
+  // findElement :: Page -> DomElement|Null
+  const element = findElement(page)
+
+  // extractJson :: DomElement -> Object|Null
+  return element ? extractJson(element) : null
+}
+```
+
+# stage 2
+
+`findElement` and `extractJson` can return null. It's a perfect case for `Maybe` !
+
+```js
+const task = async url => {
+  const page = await loadPage(url)
+
+  // findElement :: Page -> Maybe DomElement
+  // extractJson :: DomElement -> Maybe Object
+  return findElement(page)
+    .chain(extractJson)
+}
+```
+
+# stage 3
+
+why should I stop on `Maybe`. There're more fancy things!
+
+Looks like `Task` is the right one for the job.
+
+```js
+// loadPage :: String -> Task Error Page
+```
+
+# stage 4
+
+Hmm.. should `Task` return data wrapped in `Result`? Sounds quite logical!
+
+```js
+// loadPage :: String -> Task Error (Result ?? Page)
+```
+
+# stage 5
+
+Does `Task` should return `Future`... Don't think so. Actually Promise is a `Future` so I'm replacing `Task` with `Future`.
+
+# stage 6
+
+So, I have a `Future` which should return `Result`. Value of `Result` will be parsed and wrapped in `Maybe`.
+
+Doest it mean that my function returns `Future (Result Error (Maybe object))`? :o
+
+# stage 7
+
+The complexity of this thing weighs heavily on my shoulders...
+
+# stage 8
+
+Ahh! forgot that `task()` should return a promise. Way more complicated..
+
+# stage 9 - finale
+
+Fuck it! `Promise` returning `Maybe` is all I need.  
+*going back to stage 2*