- any(lst) ⇒
boolean FN.any is a function which evaluates a number of expressions and returns true if ANY of the expressions themselves are true.
Example(s):
FN.any([1 === 1, 5 === 5]);
- all(lst) ⇒
boolean FN.all is a function which evaluates a number of expressions and returns true only if ALL of the expressions are themselves true.
Example(s):
FN.all([1 === 1, 5 === 5]);
- first(lst) ⇒
object|undefined FN.first returns the first element of a list.
Example(s):
FN.first([1, 2, 3, 4, 5]);
- last(lst) ⇒
object|undefined FN.last is the inverse of FN.first and returns the final element in a list.
Example(s):
FN.last([1, 2, 3, 4, 5]);
- nth(lst, n) ⇒
object|undefined FN.nth complements FN.first and FN.last by providing a means to grab an arbitrary element in a list by numeric index.
Example(s):
FN.nth([1, 2, 3, 4, 5], 2);
- rest(lst) ⇒
array|undefined FN.rest complements FN.first by passing everything execept the first element into a callback.
Example(s):
FN.rest([1, 2, 3, 4, 5]);
- take(lst, n) ⇒
array FN.take returns a new list from the n number of elements from the list passed into it.
Example(s):
FN.take(["Lions", "Tigers", "Bears"], 2);
FN.take(FN.range(10, 0, 2), 2);
- if(cond, cb) ⇒
object|undefined FN.if is a single branch function. It expects a callback and a single boolean expression.
NOTE: FN.any and FN.all can be used here.
Example(s):
FN.if(true, () => { console.log("Is true"); });
FN.if(FN.any([1 === 1, 2 === 2]), () => { console.log("Is true"); });
- ifElse(cond, cb1, cb2) ⇒
object|undefined FN.ifElse expands upon FN.if by permitting the user to provide a second callback function to be executed in the event that the if expression evaluates to false.
NOTE: Multiple FN.fElse can be nested inside of the callback functions.
Example(s):
FN.ifElse(true, () => { console.log("Is true"); },() => { console.log("Is false"); });
FN.ifElse(FN.all([1 === 1, 2 === 2]), () => { console.log("Is true"); }, () => { console.log("Is false"); });
- let(objectContext, cb) ⇒
object FN.let creates a new isolated execution context with a set of values initilised within the context and visible only for the duration of the callback function. Note that it acts as a closure and does have access to outer variables.
Example(s):
FN.let({"age": 29, "name": "Neil Munro"}, function() { console.log("Hi my name is " + this.name + " and I am " + this.age + " years old."); });
- range([start], stop, [step]) ⇒
array FN.range generates and array of numeric values based on criteria that the programmer enters.
Example(s):
FN.range(0, 10, 1);
- cond(...lst) ⇒
object|undefined FN.cond is analogous to a switch statement. It evaluates each expression in turn until it first the first one that evaluates to true and runs its acompanying function.
Example(s):
FN.cond( 1 === 2, () => { console.log("first"); }, 2 === 3, () => { console.log("second"); }, "tmp" === "tmp", () => { console.log("third"); } );
- everyOther(cb, arr, step) ⇒
undefined FN.everyOther is a function for applying the callback for every N elemet in an array.
Example(s):
FN.everyOther((elm) => { console.log(elm); }, [0, 1, 2, 3, 4, 5, 6], 2);
- case(val, ...lst) ⇒
object|undefined FN.case is a function that evaluates a set of conditions against a sentinal condition, the acompanying function is ran. A default condition can be passed and a final callback passed for the default condition.
Example(s):
FN.case(9, 1, () => 12, 2, () => 22, 3, () => 3*2, FN.default, () => 19);
- sum(lst) ⇒
number|undefined FN.sum is a function that takes a variable number of arguments and returns the sum of all arguments all arguments must be numbers, if not undefined is returned.
Example(s):
FN.sum([1, 2, 3, 4, 5]);
Kind: global class
Author: Neil Munro neilmunro@gmail.com
FN is a functional library providing functions inspired (ripped off) by LISP/Clojure.
No, I have no shame.
This is kinda just research, experimenting with functional programming in JS. If you however find this library useful let me know and I'll keep working on it, if you have suggestions, I might even incorporate your ideas.
This is designed to be used from within ES6. Other older versions of ES may not work properly.
Copyright (c) Neil Munro 2015-2016.
FN.any is a function which evaluates a number of expressions and returns true if ANY of the expressions themselves are true.
Example(s):
FN.any([1 === 1, 5 === 5]);
Kind: global function
Returns: boolean - The result of any of the expressions being true.
| Param | Type | Description |
|---|---|---|
| lst | array |
The list of boolean expressions to FN.any. |
FN.all is a function which evaluates a number of expressions and returns true only if ALL of the expressions are themselves true.
Example(s):
FN.all([1 === 1, 5 === 5]);
Kind: global function
Returns: boolean - The result of all of the expressions being true.
| Param | Type | Description |
|---|---|---|
| lst | array |
The list of boolean expressions to FN.all. |
FN.first returns the first element of a list.
Example(s):
FN.first([1, 2, 3, 4, 5]);
Kind: global function
Returns: object | undefined - The first element of the list or undefined.
| Param | Type | Description |
|---|---|---|
| lst | array |
The list to get the first element of. |
FN.last is the inverse of FN.first and returns the final element in a list.
Example(s):
FN.last([1, 2, 3, 4, 5]);
Kind: global function
Returns: object | undefined - The last element of the list or undefined.
See: FN.first
| Param | Type | Description |
|---|---|---|
| lst | array |
The arguments to FN.last. |
FN.nth complements FN.first and FN.last by providing a means to grab an arbitrary element in a list by numeric index.
Example(s):
FN.nth([1, 2, 3, 4, 5], 2);
Kind: global function
Returns: object | undefined - The nth element of the list or undefined.
See
- FN.first
- FN.last
| Param | Type | Description |
|---|---|---|
| lst | array |
The list to get the nth element of. |
| n | number |
The nth element in the list to try and get. |
FN.rest complements FN.first by passing everything execept the first element into a callback.
Example(s):
FN.rest([1, 2, 3, 4, 5]);
Kind: global function
Returns: array | undefined - The rest of the list or undefined.
See: FN.first
| Param | Type | Description |
|---|---|---|
| lst | array |
The arguments to FN.rest. |
FN.take returns a new list from the n number of elements from the list passed into it.
Example(s):
FN.take(["Lions", "Tigers", "Bears"], 2);
FN.take(FN.range(10, 0, 2), 2);
Kind: global function
Returns: array - A new list made up of the n number of elements, if n is bigger than the list the whole list is returned.
| Param | Type | Description |
|---|---|---|
| lst | array |
The arguments to FN.take. |
| n | number |
The number of elements to take from the array lst. |
FN.if is a single branch function. It expects a callback and a single boolean expression.
NOTE: FN.any and FN.all can be used here.
Example(s):
FN.if(true, () => { console.log("Is true"); });
FN.if(FN.any([1 === 1, 2 === 2]), () => { console.log("Is true"); });
Kind: global function
Returns: object | undefined - The result of the callback or undefined.
See: FN.ifElse
| Param | Type | Description |
|---|---|---|
| cond | boolean |
The single boolean expression to FN.if. |
| cb | function |
The callback to execute if true. |
FN.ifElse expands upon FN.if by permitting the user to provide a second callback function to be executed in the event that the if expression evaluates to false.
NOTE: Multiple FN.fElse can be nested inside of the callback functions.
Example(s):
FN.ifElse(true, () => { console.log("Is true"); },() => { console.log("Is false"); });
FN.ifElse(FN.all([1 === 1, 2 === 2]), () => { console.log("Is true"); }, () => { console.log("Is false"); });
Kind: global function
Returns: object | undefined - The result of the callback or undefined.
See: FN.if
| Param | Type | Description |
|---|---|---|
| cond | boolean |
The boolean expression to FN.ifElse. |
| cb1 | function |
The callback to execute in the form: () => {...} if true. |
| cb2 | function |
The callback to execute in the form: () => {...} if false. |
FN.let creates a new isolated execution context with a set of values initilised within the context and visible only for the duration of the callback function. Note that it acts as a closure and does have access to outer variables.
Example(s):
FN.let({"age": 29, "name": "Neil Munro"}, function() { console.log("Hi my name is " + this.name + " and I am " + this.age + " years old."); });
Kind: global function
Returns: object - The return value of the callback function.
See: FN.if
| Param | Type | Description |
|---|---|---|
| objectContext | object |
An object containing the key/value pairs |
| cb | function |
The callback to execute in the form: function() {...}. You MUST use the original function() {} form as these bind a 'this' value to the scope that FN.let provides. that are to be created inside the execution context. |
FN.range generates and array of numeric values based on criteria that the programmer enters.
Example(s):
FN.range(0, 10, 1);
Kind: global function
Returns: array - The array built from lst.
| Param | Type | Description |
|---|---|---|
| [start] | number |
The number to start from. |
| stop | number |
The number to go to. |
| [step] | number |
The number of steps/intervals. |
FN.cond is analogous to a switch statement. It evaluates each expression in turn until it first the first one that evaluates to true and runs its acompanying function.
Example(s):
FN.cond( 1 === 2, () => { console.log("first"); }, 2 === 3, () => { console.log("second"); }, "tmp" === "tmp", () => { console.log("third"); } );
Kind: global function
Returns: object | undefined - The result of the executed function or undefined.
| Param | Type | Description |
|---|---|---|
| ...lst | boolean | function |
An array of expression/function pairs to evaluate/run. |
FN.everyOther is a function for applying the callback for every N elemet in an array.
Example(s):
FN.everyOther((elm) => { console.log(elm); }, [0, 1, 2, 3, 4, 5, 6], 2);
Kind: global function
Returns: undefined - everyOther does not return anything it applies a callback for
every other element in a list.
| Param | Type | Description |
|---|---|---|
| cb | function |
The function to apply to n elements of the array. |
| arr | array |
The array containing the elements to apply the function to. |
| step | number |
The interval of steps to apply a function to. |
FN.case is a function that evaluates a set of conditions against a sentinal condition, the acompanying function is ran. A default condition can be passed and a final callback passed for the default condition.
Example(s):
FN.case(9, 1, () => 12, 2, () => 22, 3, () => 3*2, FN.default, () => 19);
Kind: global function
Returns: object | undefined - The result of the executed function or undefined.
| Param | Type | Description |
|---|---|---|
| val | number | string |
The sentinal condition. |
| ...lst | number | string | boolean | function |
The condition/function pairs to check against the sentinal and execute, if true. |
FN.sum is a function that takes a variable number of arguments and returns the sum of all arguments all arguments must be numbers, if not undefined is returned.
Example(s):
FN.sum([1, 2, 3, 4, 5]);
Kind: global function
Returns: number | undefined - The sum of the provided arguments.
| Param | Type | Description |
|---|---|---|
| lst | array |
The list of numbers to sum. |