Use Buffers to Store Values Until a Condition is Met
Buffers give you chance to gather values together until your ready to work with them. This pattern can be used for calculations, string manipulations, and many other scenarios.
Consider a solution where splitter argument is a function instead of a value. How could you capture the condition in that function rather than the way it was implemented in this lesson
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John Lindquist: [0:00] Let's create a split operator. I'll select all of this, duplicate it, and then name this split, and it was passing a value to split on which we'll call the splitter. Then implement the behavior that we want. Again, it's just writing something in the body of this function that defines what we want.
[0:18] I'm going to create a buffer. If the value is the same as the splitter, then I want to push out the buffer. Otherwise, just push the value into the buffer. Then we'd also have to clear the buffer after we push it out.
[0:37] Let's go and import this into our operators. I'm going to get rid of modify, so put the modify here. Our project currently looks like this where it's doing one letter at a time. Now, when I import split, and I say splitOnSpace, and I hit save, you'll see we get an array with the characters of Hello. Our buffer pushed in HELLO and then it shut down. We missed out on getting John.
[1:08] This is a scenario where we want a custom done behavior. In my createOperator there, I'm going to just swap that out for curry so that if value = done, then I can do this same behavior here where I push out the buffer, clear it out, and then send along done.
[1:30] Now if I hit Save, you'll see I get an array of Hello and an array of John. Let's go ahead and join these together. In the logic, there would be I want to map. At this point, these are arrays. I'll say map this array to Array.join. I'll hit Save. Now we'll get Hello and John.
[1:55] Finally, I'm just going to delete modify here. We only use that as a generic teaching tool where something like an appendOperator would be more appropriate.