Transform ​

compose() ​

Performs function composition from right to left (the output of the function on the right becomes the input to the function on the left).

• Type

• Details

Takes several functions as arguments. The return value is a function with the same number of arguments as the last argument, which is the result of the function composition from right to left of all the functions in the arguments.

Obviously, except for the last argument, which may be a multi-argument function, all other arguments should be unary functions.

• Example

const div_and_add = compose(add(1), mul(0.5));

div_and_add(229026); //114514

const div_and_add = compose(add(1), mul(0.5));

div_and_add(229026); //114514

pipe() ​

Performs function composition from left to right (the output of the function on the left becomes the input to the function on the right).

• Type

• Details

Takes several functions as arguments. The return value is a function with the same number of arguments as the first argument, which is the result of the function composition from left to right of all the functions in the arguments.

Obviously, except for the first argument, which may be a multi-argument function, all other arguments should be unary functions.

• Example

const div_and_add = pipe(mul(0.5), add(1));

div_and_add(229026); //114514

const div_and_add = pipe(mul(0.5), add(1));

div_and_add(229026); //114514

call() ​

Executes an existing function.

• Type

• Details

The first argument is the function to be executed. The second argument represents the parameters for the function to be executed, passed as an array.

• Example

const foo = (a, b) => a + b;

call(foo, ['114', '514']); //"114514"

const foo = (a, b) => a + b;

call(foo, ['114', '514']); //"114514"

andThen() ​

Adds a function after a Promise, equivalent to Promise.then.

• Type

• Details

The first argument is a function, and the second argument passes in the Promise object to be operated on.

• Example

const fetch = () =>
	new Promise((resolve, reject) => {
		//...do sth.
	});

await pipe(fetch, andThen(toUpper));

const fetch = () =>
	new Promise((resolve, reject) => {
		//...do sth.
	});

await pipe(fetch, andThen(toUpper));

tryCatch() ​

Function wrapper for error detection.

• Type

• Details

The first argument passes in a function tryer, and the second argument passes in a function reject. The return value is the curried wrapper of the tryer function.

tryCatch essentially creates a wrapper for tryer, returning the normal output of tryer when no error occurs. Otherwise, it will pass both the error and the arguments given to tryer to reject.

• Example

const foo = tryCatch(div(1), always('hello'));
foo(1); //1
foo(0); //hello/INF

const foo = tryCatch(div(1), always('hello'));
foo(1); //1
foo(0); //hello/INF