664 lines
18 KiB
JavaScript
664 lines
18 KiB
JavaScript
import { fromEquals } from './Eq';
|
|
import { fromOption as fromOption_, fromOptionK as fromOptionK_, fromPredicate as fromPredicate_ } from './FromEither';
|
|
import { identity, pipe } from './function';
|
|
import { flap as flap_ } from './Functor';
|
|
import * as _ from './internal';
|
|
// -------------------------------------------------------------------------------------
|
|
// refinements
|
|
// -------------------------------------------------------------------------------------
|
|
/**
|
|
* Returns `true` if the these is an instance of `Left`, `false` otherwise
|
|
*
|
|
* @category refinements
|
|
* @since 2.0.0
|
|
*/
|
|
export var isLeft = function (fa) { return fa._tag === 'Left'; };
|
|
/**
|
|
* Returns `true` if the these is an instance of `Right`, `false` otherwise
|
|
*
|
|
* @category refinements
|
|
* @since 2.0.0
|
|
*/
|
|
export var isRight = function (fa) { return fa._tag === 'Right'; };
|
|
/**
|
|
* Returns `true` if the these is an instance of `Both`, `false` otherwise
|
|
*
|
|
* @category refinements
|
|
* @since 2.0.0
|
|
*/
|
|
export function isBoth(fa) {
|
|
return fa._tag === 'Both';
|
|
}
|
|
// -------------------------------------------------------------------------------------
|
|
// constructors
|
|
// -------------------------------------------------------------------------------------
|
|
/**
|
|
* @category constructors
|
|
* @since 2.0.0
|
|
*/
|
|
export function left(left) {
|
|
return { _tag: 'Left', left: left };
|
|
}
|
|
/**
|
|
* @category constructors
|
|
* @since 2.0.0
|
|
*/
|
|
export function right(right) {
|
|
return { _tag: 'Right', right: right };
|
|
}
|
|
/**
|
|
* @category constructors
|
|
* @since 2.0.0
|
|
*/
|
|
export function both(left, right) {
|
|
return { _tag: 'Both', left: left, right: right };
|
|
}
|
|
/**
|
|
* Less strict version of [`match`](#match).
|
|
*
|
|
* The `W` suffix (short for **W**idening) means that the handler return types will be merged.
|
|
*
|
|
* @category pattern matching
|
|
* @since 2.10.0
|
|
*/
|
|
export var matchW = function (onLeft, onRight, onBoth) {
|
|
return function (fa) {
|
|
switch (fa._tag) {
|
|
case 'Left':
|
|
return onLeft(fa.left);
|
|
case 'Right':
|
|
return onRight(fa.right);
|
|
case 'Both':
|
|
return onBoth(fa.left, fa.right);
|
|
}
|
|
};
|
|
};
|
|
/**
|
|
* Alias of [`matchW`](#matchw).
|
|
*
|
|
* @category pattern matching
|
|
* @since 2.10.0
|
|
*/
|
|
export var foldW = matchW;
|
|
/**
|
|
* @category pattern matching
|
|
* @since 2.10.0
|
|
*/
|
|
export var match = matchW;
|
|
/**
|
|
* Alias of [`match`](#match).
|
|
*
|
|
* @category pattern matching
|
|
* @since 2.0.0
|
|
*/
|
|
export var fold = match;
|
|
/**
|
|
* @since 2.4.0
|
|
*/
|
|
export var swap = match(right, left, function (e, a) { return both(a, e); });
|
|
/**
|
|
* @category instances
|
|
* @since 2.0.0
|
|
*/
|
|
export function getShow(SE, SA) {
|
|
return {
|
|
show: match(function (l) { return "left(".concat(SE.show(l), ")"); }, function (a) { return "right(".concat(SA.show(a), ")"); }, function (l, a) { return "both(".concat(SE.show(l), ", ").concat(SA.show(a), ")"); })
|
|
};
|
|
}
|
|
/**
|
|
* @category instances
|
|
* @since 2.0.0
|
|
*/
|
|
export function getEq(EE, EA) {
|
|
return fromEquals(function (x, y) {
|
|
return isLeft(x)
|
|
? isLeft(y) && EE.equals(x.left, y.left)
|
|
: isRight(x)
|
|
? isRight(y) && EA.equals(x.right, y.right)
|
|
: isBoth(y) && EE.equals(x.left, y.left) && EA.equals(x.right, y.right);
|
|
});
|
|
}
|
|
/**
|
|
* @category instances
|
|
* @since 2.0.0
|
|
*/
|
|
export function getSemigroup(SE, SA) {
|
|
return {
|
|
concat: function (x, y) {
|
|
return isLeft(x)
|
|
? isLeft(y)
|
|
? left(SE.concat(x.left, y.left))
|
|
: isRight(y)
|
|
? both(x.left, y.right)
|
|
: both(SE.concat(x.left, y.left), y.right)
|
|
: isRight(x)
|
|
? isLeft(y)
|
|
? both(y.left, x.right)
|
|
: isRight(y)
|
|
? right(SA.concat(x.right, y.right))
|
|
: both(y.left, SA.concat(x.right, y.right))
|
|
: isLeft(y)
|
|
? both(SE.concat(x.left, y.left), x.right)
|
|
: isRight(y)
|
|
? both(x.left, SA.concat(x.right, y.right))
|
|
: both(SE.concat(x.left, y.left), SA.concat(x.right, y.right));
|
|
}
|
|
};
|
|
}
|
|
/**
|
|
* @category instances
|
|
* @since 2.10.0
|
|
*/
|
|
export var getApply = function (S) { return ({
|
|
URI: URI,
|
|
_E: undefined,
|
|
map: _map,
|
|
ap: function (fab, fa) {
|
|
return isLeft(fab)
|
|
? isLeft(fa)
|
|
? left(S.concat(fab.left, fa.left))
|
|
: isRight(fa)
|
|
? left(fab.left)
|
|
: left(S.concat(fab.left, fa.left))
|
|
: isRight(fab)
|
|
? isLeft(fa)
|
|
? left(fa.left)
|
|
: isRight(fa)
|
|
? right(fab.right(fa.right))
|
|
: both(fa.left, fab.right(fa.right))
|
|
: isLeft(fa)
|
|
? left(S.concat(fab.left, fa.left))
|
|
: isRight(fa)
|
|
? both(fab.left, fab.right(fa.right))
|
|
: both(S.concat(fab.left, fa.left), fab.right(fa.right));
|
|
}
|
|
}); };
|
|
/**
|
|
* @category instances
|
|
* @since 2.7.0
|
|
*/
|
|
export function getApplicative(S) {
|
|
var A = getApply(S);
|
|
return {
|
|
URI: URI,
|
|
_E: undefined,
|
|
map: _map,
|
|
ap: A.ap,
|
|
of: of
|
|
};
|
|
}
|
|
/**
|
|
* @category instances
|
|
* @since 2.10.0
|
|
*/
|
|
export function getChain(S) {
|
|
var A = getApply(S);
|
|
var chain = function (ma, f) {
|
|
if (isLeft(ma)) {
|
|
return ma;
|
|
}
|
|
if (isRight(ma)) {
|
|
return f(ma.right);
|
|
}
|
|
var fb = f(ma.right);
|
|
return isLeft(fb)
|
|
? left(S.concat(ma.left, fb.left))
|
|
: isRight(fb)
|
|
? both(ma.left, fb.right)
|
|
: both(S.concat(ma.left, fb.left), fb.right);
|
|
};
|
|
return {
|
|
URI: URI,
|
|
_E: undefined,
|
|
map: _map,
|
|
ap: A.ap,
|
|
chain: chain
|
|
};
|
|
}
|
|
/**
|
|
* @category instances
|
|
* @since 2.0.0
|
|
*/
|
|
export function getMonad(S) {
|
|
var C = getChain(S);
|
|
return {
|
|
URI: URI,
|
|
_E: undefined,
|
|
map: _map,
|
|
of: of,
|
|
ap: C.ap,
|
|
chain: C.chain,
|
|
throwError: left
|
|
};
|
|
}
|
|
/**
|
|
* Returns an `E` value if possible
|
|
*
|
|
* @example
|
|
* import { getLeft, left, right, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(getLeft(left('a')), some('a'))
|
|
* assert.deepStrictEqual(getLeft(right(1)), none)
|
|
* assert.deepStrictEqual(getLeft(both('a', 1)), some('a'))
|
|
*
|
|
* @category conversions
|
|
* @since 2.0.0
|
|
*/
|
|
export function getLeft(fa) {
|
|
return isLeft(fa) ? _.some(fa.left) : isRight(fa) ? _.none : _.some(fa.left);
|
|
}
|
|
/**
|
|
* Returns an `A` value if possible
|
|
*
|
|
* @example
|
|
* import { getRight, left, right, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(getRight(left('a')), none)
|
|
* assert.deepStrictEqual(getRight(right(1)), some(1))
|
|
* assert.deepStrictEqual(getRight(both('a', 1)), some(1))
|
|
*
|
|
* @category conversions
|
|
* @since 2.0.0
|
|
*/
|
|
export function getRight(fa) {
|
|
return isLeft(fa) ? _.none : isRight(fa) ? _.some(fa.right) : _.some(fa.right);
|
|
}
|
|
// TODO: make lazy in v3
|
|
/**
|
|
* @example
|
|
* import { leftOrBoth, left, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(leftOrBoth('a')(none), left('a'))
|
|
* assert.deepStrictEqual(leftOrBoth('a')(some(1)), both('a', 1))
|
|
*
|
|
* @category constructors
|
|
* @since 2.0.0
|
|
*/
|
|
export function leftOrBoth(e) {
|
|
return function (ma) { return (_.isNone(ma) ? left(e) : both(e, ma.value)); };
|
|
}
|
|
// TODO: make lazy in v3
|
|
/**
|
|
* @example
|
|
* import { rightOrBoth, right, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(rightOrBoth(1)(none), right(1))
|
|
* assert.deepStrictEqual(rightOrBoth(1)(some('a')), both('a', 1))
|
|
*
|
|
* @category constructors
|
|
* @since 2.0.0
|
|
*/
|
|
export function rightOrBoth(a) {
|
|
return function (me) { return (_.isNone(me) ? right(a) : both(me.value, a)); };
|
|
}
|
|
/**
|
|
* Returns the `E` value if and only if the value is constructed with `Left`
|
|
*
|
|
* @example
|
|
* import { getLeftOnly, left, right, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(getLeftOnly(left('a')), some('a'))
|
|
* assert.deepStrictEqual(getLeftOnly(right(1)), none)
|
|
* assert.deepStrictEqual(getLeftOnly(both('a', 1)), none)
|
|
*
|
|
* @category conversions
|
|
* @since 2.0.0
|
|
*/
|
|
export function getLeftOnly(fa) {
|
|
return isLeft(fa) ? _.some(fa.left) : _.none;
|
|
}
|
|
/**
|
|
* Returns the `A` value if and only if the value is constructed with `Right`
|
|
*
|
|
* @example
|
|
* import { getRightOnly, left, right, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(getRightOnly(left('a')), none)
|
|
* assert.deepStrictEqual(getRightOnly(right(1)), some(1))
|
|
* assert.deepStrictEqual(getRightOnly(both('a', 1)), none)
|
|
*
|
|
* @category conversions
|
|
* @since 2.0.0
|
|
*/
|
|
export function getRightOnly(fa) {
|
|
return isRight(fa) ? _.some(fa.right) : _.none;
|
|
}
|
|
/**
|
|
* Takes a pair of `Option`s and attempts to create a `These` from them
|
|
*
|
|
* @example
|
|
* import { fromOptions, left, right, both } from 'fp-ts/These'
|
|
* import { none, some } from 'fp-ts/Option'
|
|
*
|
|
* assert.deepStrictEqual(fromOptions(none, none), none)
|
|
* assert.deepStrictEqual(fromOptions(some('a'), none), some(left('a')))
|
|
* assert.deepStrictEqual(fromOptions(none, some(1)), some(right(1)))
|
|
* assert.deepStrictEqual(fromOptions(some('a'), some(1)), some(both('a', 1)))
|
|
*
|
|
* @category conversions
|
|
* @since 2.0.0
|
|
*/
|
|
export var fromOptions = function (fe, fa) {
|
|
return _.isNone(fe)
|
|
? _.isNone(fa)
|
|
? _.none
|
|
: _.some(right(fa.value))
|
|
: _.isNone(fa)
|
|
? _.some(left(fe.value))
|
|
: _.some(both(fe.value, fa.value));
|
|
};
|
|
var _map = function (fa, f) { return pipe(fa, map(f)); };
|
|
/* istanbul ignore next */
|
|
var _bimap = function (fa, f, g) { return pipe(fa, bimap(f, g)); };
|
|
/* istanbul ignore next */
|
|
var _mapLeft = function (fa, f) { return pipe(fa, mapLeft(f)); };
|
|
/* istanbul ignore next */
|
|
var _reduce = function (fa, b, f) { return pipe(fa, reduce(b, f)); };
|
|
/* istanbul ignore next */
|
|
var _foldMap = function (M) {
|
|
var foldMapM = foldMap(M);
|
|
return function (fa, f) { return pipe(fa, foldMapM(f)); };
|
|
};
|
|
/* istanbul ignore next */
|
|
var _reduceRight = function (fa, b, f) { return pipe(fa, reduceRight(b, f)); };
|
|
/* istanbul ignore next */
|
|
var _traverse = function (F) {
|
|
var traverseF = traverse(F);
|
|
return function (ta, f) { return pipe(ta, traverseF(f)); };
|
|
};
|
|
/**
|
|
* Map a pair of functions over the two type arguments of the bifunctor.
|
|
*
|
|
* @category mapping
|
|
* @since 2.0.0
|
|
*/
|
|
export var bimap = function (f, g) { return function (fa) {
|
|
return isLeft(fa) ? left(f(fa.left)) : isRight(fa) ? right(g(fa.right)) : both(f(fa.left), g(fa.right));
|
|
}; };
|
|
/**
|
|
* Map a function over the first type argument of a bifunctor.
|
|
*
|
|
* @category error handling
|
|
* @since 2.0.0
|
|
*/
|
|
export var mapLeft = function (f) { return function (fa) {
|
|
return isLeft(fa) ? left(f(fa.left)) : isBoth(fa) ? both(f(fa.left), fa.right) : fa;
|
|
}; };
|
|
/**
|
|
* `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 mapping
|
|
* @since 2.0.0
|
|
*/
|
|
export var map = function (f) { return function (fa) {
|
|
return isLeft(fa) ? fa : isRight(fa) ? right(f(fa.right)) : both(fa.left, f(fa.right));
|
|
}; };
|
|
/**
|
|
* @category folding
|
|
* @since 2.0.0
|
|
*/
|
|
export var reduce = function (b, f) { return function (fa) {
|
|
return isLeft(fa) ? b : f(b, fa.right);
|
|
}; };
|
|
/**
|
|
* @category folding
|
|
* @since 2.0.0
|
|
*/
|
|
export var foldMap = function (M) { return function (f) { return function (fa) {
|
|
return isLeft(fa) ? M.empty : f(fa.right);
|
|
}; }; };
|
|
/**
|
|
* @category folding
|
|
* @since 2.0.0
|
|
*/
|
|
export var reduceRight = function (b, f) { return function (fa) {
|
|
return isLeft(fa) ? b : f(fa.right, b);
|
|
}; };
|
|
/**
|
|
* @category traversing
|
|
* @since 2.6.3
|
|
*/
|
|
export var traverse = function (F) {
|
|
return function (f) {
|
|
return function (ta) {
|
|
return isLeft(ta) ? F.of(ta) : isRight(ta) ? F.map(f(ta.right), right) : F.map(f(ta.right), function (b) { return both(ta.left, b); });
|
|
};
|
|
};
|
|
};
|
|
/**
|
|
* @category traversing
|
|
* @since 2.6.3
|
|
*/
|
|
export var sequence = function (F) {
|
|
return function (ta) {
|
|
return isLeft(ta) ? F.of(ta) : isRight(ta) ? F.map(ta.right, right) : F.map(ta.right, function (b) { return both(ta.left, b); });
|
|
};
|
|
};
|
|
/**
|
|
* @category constructors
|
|
* @since 2.0.0
|
|
*/
|
|
export var of = right;
|
|
/**
|
|
* @category type lambdas
|
|
* @since 2.0.0
|
|
*/
|
|
export var URI = 'These';
|
|
/**
|
|
* @category instances
|
|
* @since 2.7.0
|
|
*/
|
|
export var Functor = {
|
|
URI: URI,
|
|
map: _map
|
|
};
|
|
/**
|
|
* @category mapping
|
|
* @since 2.10.0
|
|
*/
|
|
export var flap = /*#__PURE__*/ flap_(Functor);
|
|
/**
|
|
* @category instances
|
|
* @since 2.10.0
|
|
*/
|
|
export var Pointed = {
|
|
URI: URI,
|
|
of: of
|
|
};
|
|
/**
|
|
* @category instances
|
|
* @since 2.7.0
|
|
*/
|
|
export var Bifunctor = {
|
|
URI: URI,
|
|
bimap: _bimap,
|
|
mapLeft: _mapLeft
|
|
};
|
|
/**
|
|
* @category instances
|
|
* @since 2.11.0
|
|
*/
|
|
export var FromThese = {
|
|
URI: URI,
|
|
fromThese: identity
|
|
};
|
|
/**
|
|
* @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 2.10.0
|
|
*/
|
|
export var FromEither = {
|
|
URI: URI,
|
|
fromEither: identity
|
|
};
|
|
/**
|
|
* @category lifting
|
|
* @since 2.13.0
|
|
*/
|
|
export var fromPredicate = /*#__PURE__*/ fromPredicate_(FromEither);
|
|
/**
|
|
* @category conversions
|
|
* @since 2.10.0
|
|
*/
|
|
export var fromOption =
|
|
/*#__PURE__*/ fromOption_(FromEither);
|
|
/**
|
|
* @category lifting
|
|
* @since 2.10.0
|
|
*/
|
|
export var fromOptionK =
|
|
/*#__PURE__*/ fromOptionK_(FromEither);
|
|
// -------------------------------------------------------------------------------------
|
|
// utils
|
|
// -------------------------------------------------------------------------------------
|
|
/**
|
|
* @since 2.11.0
|
|
*/
|
|
export var elem = function (E) {
|
|
return function (a) {
|
|
return function (ma) {
|
|
return isLeft(ma) ? false : E.equals(a, ma.right);
|
|
};
|
|
};
|
|
};
|
|
/**
|
|
* @since 2.11.0
|
|
*/
|
|
export var exists = function (predicate) {
|
|
return function (ma) {
|
|
return isLeft(ma) ? false : predicate(ma.right);
|
|
};
|
|
};
|
|
/**
|
|
* @example
|
|
* import { toTuple2, left, right, both } from 'fp-ts/These'
|
|
*
|
|
* assert.deepStrictEqual(toTuple2(() => 'a', () => 1)(left('b')), ['b', 1])
|
|
* assert.deepStrictEqual(toTuple2(() => 'a', () => 1)(right(2)), ['a', 2])
|
|
* assert.deepStrictEqual(toTuple2(() => 'a', () => 1)(both('b', 2)), ['b', 2])
|
|
*
|
|
* @category conversions
|
|
* @since 2.10.0
|
|
*/
|
|
export var toTuple2 = function (e, a) {
|
|
return function (fa) {
|
|
return isLeft(fa) ? [fa.left, a()] : isRight(fa) ? [e(), fa.right] : [fa.left, fa.right];
|
|
};
|
|
};
|
|
// -------------------------------------------------------------------------------------
|
|
// deprecated
|
|
// -------------------------------------------------------------------------------------
|
|
/**
|
|
* Use [`toTuple2`](#totuple2) instead.
|
|
*
|
|
* @category zone of death
|
|
* @since 2.0.0
|
|
* @deprecated
|
|
*/
|
|
export var toTuple = function (e, a) {
|
|
return toTuple2(function () { return e; }, function () { return a; });
|
|
};
|
|
/**
|
|
* @since 2.11.0
|
|
*/
|
|
export var ApT = /*#__PURE__*/ of(_.emptyReadonlyArray);
|
|
// -------------------------------------------------------------------------------------
|
|
// array utils
|
|
// -------------------------------------------------------------------------------------
|
|
/**
|
|
* Equivalent to `ReadonlyNonEmptyArray#traverseWithIndex(getApplicative(S))`.
|
|
*
|
|
* @category traversing
|
|
* @since 2.11.0
|
|
*/
|
|
export var traverseReadonlyNonEmptyArrayWithIndex = function (S) {
|
|
return function (f) {
|
|
return function (as) {
|
|
var e = _.none;
|
|
var t = f(0, _.head(as));
|
|
if (isLeft(t)) {
|
|
return t;
|
|
}
|
|
if (isBoth(t)) {
|
|
e = _.some(t.left);
|
|
}
|
|
var out = [t.right];
|
|
for (var i = 1; i < as.length; i++) {
|
|
var t_1 = f(i, as[i]);
|
|
if (isLeft(t_1)) {
|
|
return t_1;
|
|
}
|
|
if (isBoth(t_1)) {
|
|
e = _.isNone(e) ? _.some(t_1.left) : _.some(S.concat(e.value, t_1.left));
|
|
}
|
|
out.push(t_1.right);
|
|
}
|
|
return _.isNone(e) ? right(out) : both(e.value, out);
|
|
};
|
|
};
|
|
};
|
|
/**
|
|
* Equivalent to `ReadonlyArray#traverseWithIndex(getApplicative(S))`.
|
|
*
|
|
* @category traversing
|
|
* @since 2.11.0
|
|
*/
|
|
export var traverseReadonlyArrayWithIndex = function (S) {
|
|
return function (f) {
|
|
var g = traverseReadonlyNonEmptyArrayWithIndex(S)(f);
|
|
return function (as) { return (_.isNonEmpty(as) ? g(as) : ApT); };
|
|
};
|
|
};
|
|
// -------------------------------------------------------------------------------------
|
|
// deprecated
|
|
// -------------------------------------------------------------------------------------
|
|
/**
|
|
* This instance is deprecated, use small, specific instances instead.
|
|
* For example if a function needs a `Functor` instance, pass `T.Functor` instead of `T.these`
|
|
* (where `T` is from `import T from 'fp-ts/These'`)
|
|
*
|
|
* @category zone of death
|
|
* @since 2.0.0
|
|
* @deprecated
|
|
*/
|
|
export var these = {
|
|
URI: URI,
|
|
map: _map,
|
|
bimap: _bimap,
|
|
mapLeft: _mapLeft,
|
|
reduce: _reduce,
|
|
foldMap: _foldMap,
|
|
reduceRight: _reduceRight,
|
|
traverse: _traverse,
|
|
sequence: sequence
|
|
};
|