fp-ts
Version:
Functional programming in TypeScript
314 lines (313 loc) • 7.48 kB
JavaScript
import { tailRec } from './ChainRec';
import { identity as id, pipe, bind_, bindTo_, flow } from './function';
// -------------------------------------------------------------------------------------
// non-pipeables
// -------------------------------------------------------------------------------------
var map_ = function (fa, f) { return pipe(fa, map(f)); };
var ap_ = function (fab, fa) { return pipe(fab, ap(fa)); };
var chain_ = function (ma, f) { return pipe(ma, chain(f)); };
/* istanbul ignore next */
var reduce_ = function (fa, b, f) { return pipe(fa, reduce(b, f)); };
/* istanbul ignore next */
var foldMap_ = function (M) { return function (fa, f) { return pipe(fa, foldMap(M)(f)); }; };
/* istanbul ignore next */
var reduceRight_ = function (fa, b, f) { return pipe(fa, reduceRight(b, f)); };
/* istanbul ignore next */
var alt_ = function (fa, that) { return pipe(fa, alt(that)); };
/* istanbul ignore next */
var extend_ = function (wa, f) { return pipe(wa, extend(f)); };
/* istanbul ignore next */
var traverse_ = function (F) {
var traverseF = traverse(F);
return function (ta, f) { return pipe(ta, traverseF(f)); };
};
var chainRec_ = tailRec;
// -------------------------------------------------------------------------------------
// pipeables
// -------------------------------------------------------------------------------------
/**
* `map` can be used to turn functions `(a: A) => B` into functions `(fa: F<A>) => F<B>` whose argument and return types
* use the type constructor `F` to represent some computational context.
*
* @category Functor
* @since 2.0.0
*/
export var map = function (f) { return function (fa) { return f(fa); }; };
/**
* Apply a function to an argument under a type constructor.
*
* @category Apply
* @since 2.0.0
*/
export var ap = function (fa) { return function (fab) { return fab(fa); }; };
/**
* Combine two effectful actions, keeping only the result of the first.
*
* Derivable from `Apply`.
*
* @category combinators
* @since 2.0.0
*/
export var apFirst = function (fb) {
return flow(map(function (a) { return function () { return a; }; }), ap(fb));
};
/**
* Combine two effectful actions, keeping only the result of the second.
*
* Derivable from `Apply`.
*
* @category combinators
* @since 2.0.0
*/
export var apSecond = function (fb) {
return flow(map(function () { return function (b) { return b; }; }), ap(fb));
};
/**
* Wrap a value into the type constructor.
*
* @category Applicative
* @since 2.0.0
*/
export var of = id;
/**
* Composes computations in sequence, using the return value of one computation to determine the next computation.
*
* @category Monad
* @since 2.0.0
*/
export var chain = function (f) { return function (ma) { return f(ma); }; };
/**
* Composes computations in sequence, using the return value of one computation to determine the next computation and
* keeping only the result of the first.
*
* Derivable from `Monad`.
*
* @category combinators
* @since 2.0.0
*/
export var chainFirst = function (f) {
return chain(function (a) {
return pipe(f(a), map(function () { return a; }));
});
};
/**
* @category Extend
* @since 2.0.0
*/
export var extend = function (f) { return function (wa) { return f(wa); }; };
/**
* @category Extract
* @since 2.6.2
*/
export var extract = id;
/**
* Derivable from `Extend`.
*
* @category combinators
* @since 2.0.0
*/
export var duplicate =
/*#__PURE__*/
extend(id);
/**
* Derivable from `Monad`.
*
* @category combinators
* @since 2.0.0
*/
export var flatten =
/*#__PURE__*/
chain(id);
/**
* @category Foldable
* @since 2.0.0
*/
export var reduce = function (b, f) { return function (fa) { return f(b, fa); }; };
/**
* @category Foldable
* @since 2.0.0
*/
export var foldMap = function () { return function (f) { return function (fa) { return f(fa); }; }; };
/**
* @category Foldable
* @since 2.0.0
*/
export var reduceRight = function (b, f) { return function (fa) { return f(fa, b); }; };
/**
* @since 2.6.3
*/
export var traverse = function (F) { return function (f) { return function (ta) { return F.map(f(ta), id); }; }; };
/**
* @since 2.6.3
*/
export var sequence = function (F) { return function (ta) {
return F.map(ta, id);
}; };
/**
* Less strict version of [`alt`](#alt).
*
* @category Alt
* @since 2.9.0
*/
export var altW = function () { return id; };
/**
* Identifies an associative operation on a type constructor. It is similar to `Semigroup`, except that it applies to
* types of kind `* -> *`.
*
* @category Alt
* @since 2.0.0
*/
export var alt = altW;
// -------------------------------------------------------------------------------------
// instances
// -------------------------------------------------------------------------------------
/**
* @category instances
* @since 2.0.0
*/
export var URI = 'Identity';
/**
* @category instances
* @since 2.0.0
*/
export var getShow = id;
/**
* @category instances
* @since 2.0.0
*/
export var getEq = id;
/**
* @category instances
* @since 2.7.0
*/
export var Functor = {
URI: URI,
map: map_
};
/**
* @category instances
* @since 2.7.0
*/
export var Applicative = {
URI: URI,
map: map_,
ap: ap_,
of: of
};
/**
* @category instances
* @since 2.7.0
*/
export var Monad = {
URI: URI,
map: map_,
ap: ap_,
of: of,
chain: chain_
};
/**
* @category instances
* @since 2.7.0
*/
export var Foldable = {
URI: URI,
reduce: reduce_,
foldMap: foldMap_,
reduceRight: reduceRight_
};
/**
* @category instances
* @since 2.7.0
*/
export var Traversable = {
URI: URI,
map: map_,
reduce: reduce_,
foldMap: foldMap_,
reduceRight: reduceRight_,
traverse: traverse_,
sequence: sequence
};
/**
* @category instances
* @since 2.7.0
*/
export var Alt = {
URI: URI,
map: map_,
alt: alt_
};
/**
* @category instances
* @since 2.7.0
*/
export var Comonad = {
URI: URI,
map: map_,
extend: extend_,
extract: extract
};
/**
* @category instances
* @since 2.7.0
*/
export var ChainRec = {
URI: URI,
map: map_,
ap: ap_,
chain: chain_,
chainRec: chainRec_
};
// TODO: remove in v3
/**
* @category instances
* @since 2.0.0
*/
export var identity = {
URI: URI,
map: map_,
ap: ap_,
of: of,
chain: chain_,
reduce: reduce_,
foldMap: foldMap_,
reduceRight: reduceRight_,
traverse: traverse_,
sequence: sequence,
alt: alt_,
extract: extract,
extend: extend_,
chainRec: chainRec_
};
// -------------------------------------------------------------------------------------
// do notation
// -------------------------------------------------------------------------------------
/**
* @since 2.9.0
*/
export var Do =
/*#__PURE__*/
of({});
/**
* @since 2.8.0
*/
export var bindTo = function (name) {
return map(bindTo_(name));
};
/**
* @since 2.8.0
*/
export var bind = function (name, f) {
return chain(function (a) {
return pipe(f(a), map(function (b) { return bind_(a, name, b); }));
});
};
// -------------------------------------------------------------------------------------
// pipeable sequence S
// -------------------------------------------------------------------------------------
/**
* @since 2.8.0
*/
export var apS = function (name, fb) {
return flow(map(function (a) { return function (b) { return bind_(a, name, b); }; }), ap(fb));
};