fts-functor

Functor
===============================================================================
A functor is simply a type that can be "mapped" over. The canonical example
is mapping over a list to convert strings to integers, as in
["1", "2", "3"].map( x => Number.parseInt(x) ). Though it should be stated
that this package DOES NOT alter any built-in types.

Not every type can, or should, be mappable, but many unexpected types can be
mapped. For instance, any Monad can be mapped over. Consider that a Monad
is fundamentally a kind of container, and we can change whatever is inside
that monad with fmap.

All in all, it's not expected that the causual user will ever need to implement
a functor directly. Rather, most users will almost always consume functors
without realizing it. Authors of libraries that provide functional types
though, will likely find this library handy.

Quickstart
-------------------------------------------------------------------------------
Install with:
``
npm install --save fts-maybe
`


Import with:
`
import * as Functor from 'fts-functor';
`

Simple class implementing a functor:
`
import * as Functor from "../Functor";

class TestContainer implements Functor.Functor {
constructor(readonly value: V){}

fmap(fmapFunction: Functor.FmapFunction): TestContainer {
return new TestContainer( fmapFunction(this.value) );
}
}
`

Note, that fmap accepts a function. The function it accepts returns a new
value, which will be placed in a new container class of potentially a new type.


And here is some code that uses fmap:
`
const stringTc = new TestContainer("12")
const numberTc = stringTc.fmap( (value: string) => Number.parseInt(value) );
``