toolbox-ts v0.5.1

toolbox-ts

all / any / none / notAll

Very simple functions to express logical evaluations.
Evaluates boolean or function that returns boolean.

usage

all(
    true,
    any(
        () => false,
        notAll(true, () => false)
    ),
    none(
        false,
        () => false
    )
)) // true

Not only variable arguments but also arrays can be evaluated.

all([
    true,
    any([
        () => false,
        notAll(true, () => false)
    ]),
    none(
        false,
        () => true
    )]
) // false

Short-circuit evaluation is used.

notAll(
    true,
    false,
    () => { throw new Error("unexpected evaluation"); }
)) // true

Patterns

Makes conditions/values easy to be expressed in patterns.
(NOTE: This is probably the next best thing, as a proper separation of concern should make implementation more concise. )

Condition

• boolean
• function returns boolean (Proposition)
• function evaluates argument (Predicate)

Value

• value
• function returns value (Supplier)

usage

You can get value of the first pattern which satisfied by given value (or an undefined).

Patterns
    .of(
        [false, "some phrase"],
        [() => false, "another phrase"],
        [(target: string) => target.length > 5, returnOf(() => "yet another phrase")])
    .firstSatisfiedBy("abcdef")); // "yet another phrase"

You can define default value or its Supplier.

patterns(
    [false, "word"],
    [() => false, "some phrase"],
    [() => false, "another phrase"],
    [(target: string) => target.length < 5, returnOf(() => "yet another phrase")],
    orElse("default phrase"))
    .firstSatisfiedBy("abcdef")); // "default phrase"

Also, you can collect all values of the patterns which satisfied by given value as an array.

patterns(
    [false, "word"],
    [() => true, "some phrase"],
    [() => false, "another phrase"],
    [(target: string) => target.length > 5, returnOf(() => "yet another phrase")])
    .allSatisfiedBy("abcdef")) // ["some phrase", "yet another phrase"]

toApplicationTo

[
    (a: number): string => `${a + 1}`,
    (a: number): string => `${a + 2}`,
    (a: number): string => `${a + 3}`,
    (a: number): string => `${a + 4}`,
    (a: number): string => `${a + 5}`
]
    .map(toApplicationTo(1)) // ["2", "3", "4", "5", "6"]