fi
v1.0.16
Published
Javascript library for writing, chaining and using conditional statements in a functional way
Downloads
334
Maintainers
Readme
fi - Functional conditionals
With fi you can ignore the language constructs and write all your conditional logic in a functional way.
usage with Typescript
import { fi } from 'fi'
const myVar: string = fi(false, 'The dragon')
.elseif(
() => 1 == 2,
() => 'Vampire',
)
.else('Wargulf')
.ret()
usage with javascript / CommonJS
const { fi } = require('fi')
const myVar = fi(false, 'The dragon')
.elseif(
() => 1 == 2,
() => 'Vampire',
)
.else('Wargulf')
.ret()
Installation
The library is distributed as an npm module:
npm install fi
or
yarn add fi
Examples
Basic if statement
const getIfTrue = fi(true, 'flower puppy')
// getIfTrue() returns "flower puppy"
We can make it more interesting and add an elseif & else statements:
const getIfTrue = fi(false, 'flower puppy')
.elseif(() => false, 'something else')
.else('space pedals')
// getIfTrue() returns 'space pedals'
Even more interesting using an if-else statement as well:
With a half completed if statment, we can also start chaining more stuff to it later
const myif = fi(false, 'flower puppy').elseif(false, 'human skin')
// do some other stuff, and add to the chain:
const myVar = myif.else('crapware')
// myVar is "crapware"
Any value passed into any fi conditional or return value can be a function
Functions that don't meet a conditional are never executed, and conditionals that dont' meet a condition (like an else if conditional in an if statement evaluated as true) will also never get executed.
Ternary
The ternary variant is not chainable and does not return a function
import { ternary } from 'fi
const myVar = ternary(() => 1 > 4), () => 15, () => 42)
// myVar is 42
Switch statement using an object:
var sw = require('fi').sw
var myVar = sw('Rainbow', {
red: 'Redish',
green: 'Greenish',
blue: 'Blueish',
default: 'Some color',
})
// myVar is "Some color"
Switch statement using an array (so you can use functions as your keys):
var myVar = sw("Rainbow", [
() => "red", "Redish",
() => "green", () => "Random green",
() => "blue", "Blueish",
() => "Some color" // our default
})
// myVar is "Some color"
But.. WHY?!
- I don't know
- It could potentially lead to some interesting use cases
Author:
Arnor Heidar Sigurdsson @arnorhs on Twitter
License
MIT