Formi

Functional Programming API.

Status

API Docs

Formi exposes the Formi function.

Formi(function, args...)

Example

// define predicate function
var not = function(val) {
    return !val;
};
 
var or = function() {
    return _.some(arguments);
};
 
Formi(not, true) // ==> false
Formi(or, false, false) // ==> false
Formi(or, false, true, false) // ==> true

Formi.chain(args...)

Creates a chain for transforming data.

Example

var sum = function() {
    return _.reduce(arguments, function(total, num) {
        return total + num;
    }, 0)
}
 
var even = function() {
    return _.filter(arguments, function(val) {
        return val % 2 === 0;
    });
}
 
Formi.chain(1, 2, 3, 4)
    .pipe(even)
    .pipe(sum)
    .value(); // ==> 6

Formi.chain().pipe(func)

Define function used to transform wrapped data.

Formi.chain().value();

Return wrapped data

Formi.compose(funcs...)

Defines a composite function from a series of argument functions.

f(g(h(arg))) === Formi.compose(h, g, f)(arg)

Example

Both of these expamples define the same function.

var sumEven = Formi.compose(even, sum);
 
var sumEven = function() {
    return Formi.chain(arguments)
        .pipe(even)
        .pipe(sum)
        .value();
}
 
Formi(sumEven, 2, 3, 4, 5); //==> 6

Formi.map(func)

Defines a function that applies a function to a set of data

Example

var half = Formi.map(function(num) {
    return num / 2;
});
 
half(2) //==> 1
half(3, 4) //==> [1.5, 2]
half([4, 8]) //==> [2, 4]

Formi.reduce(func, [value])

Defines a function that reduces a set of data using a supplied function. A second argument can be provided to define an initial reduction value.

Example

var sum = Formi.reduce(function(total, num) {
    return total + num;
}, 0);
 
sum(12) //==> 12
sum(3, 4) //==> 7
sum([7, 10]) //==> 17
 
var even = Formi.reduce(function(arr, num) {
    if (num % 2) {
        arr.push(num);
    }
    return arr;
}, []);
 
even(1) //==> []
even(1, 2, 3, 4) //==> [2, 4]
even([1, 2, 3, 4]) //==> [2, 4]