feat: 🎸 add accum operator

CHANGELOG.md

@@ -18,11 +18,11 @@ All notable changes to this project will be documented in this file. See [standa
 
 ### ⚠ BREAKING CHANGES
 
-* 🧨 old curry2 became multiCurry2 to avoid collision with ramda's curryN
+* 🧨 old curry2 became curryGroups2 to avoid collision with ramda's curryN
 
 ### Features
 
-* 🎸 add multiCurry functions ([7a1eb52](https://github.com/dmitriz/cpsfy/commit/7a1eb520e1dc696742fe3940d4328d91adfc3870))
+* 🎸 add curryGroups functions ([7a1eb52](https://github.com/dmitriz/cpsfy/commit/7a1eb520e1dc696742fe3940d4328d91adfc3870))
 
 ## [3.9.0](https://github.com/dmitriz/cpsfy/compare/v3.8.0...v3.9.0) (2022-12-25)
 

index.js

@@ -2,15 +2,29 @@ const { isNil, mergeArray, inheritPrototype } = require('./utils')
 
 /* ----- General purpose utils ----- */
 
-exports.multiCurry2 = f => (...a) => (...b) => f(...a, ...b)
+exports.curryGroups2 = f => (...a) => (...b) => f(...a, ...b)
 
-exports.multiCurryN = n => f => {
+exports.curryGroupsN = n => f => {
   while(--n > 0) {
-    f = exports.multiCurry2(f)
+    f = exports.curryGroups2(f)
   }
   return f
 }
 
+/**
+ * Transform `reducer: (state,next) => state` into accumulator function updating state inside closure.
+ * 
+ * @param {Function} reducer: (state,next) -> state
+ * @returns {Function} accum(reducer): initState -> (x0,...,xn) -> reducer(prevState,x0,...,xn)
+ * 
+ * @example accumulator = accum((state,x) => state+x)
+ * acc = accumulator(5) // initialize accumulator function with initial state = 5
+ * acc(2) //=> 5+2
+ * acc(2) //=> 5+2+2
+ * acc(4) //=> 5+2+2+4
+ */
+exports.accum = reducer => state => (...vals) => {state = reducer(state, ...vals); return state}
+
 
 /**
  * Pass tuple of values to sequence of functions similar to UNIX pipe
@@ -234,7 +248,7 @@ const filter = (...preds) => {
  * @param {Function} cpsFn - CPS function.
  * @returns {Function} `scan(...reducers, init)(cpsFn)`
  *    - CPS function whose output from the first callback
- *   is the accumulated value. For each output `(y1, y2, ...)`
+ *   is the accumd value. For each output `(y1, y2, ...)`
  *   from the `n`th callback of `cpsFn, the `n`th reducer `redn`
  *   is used to compute the new acculated value
  *   `redn(acc, y1, y2, ...)`, where `acc` starts with `init`,
@@ -320,7 +334,7 @@ const ap = (...fns) => cpsFn => {
  * Lift binary function to act on values wraped inside CPS functions
  */
 exports.lift2 = f => (F1, F2) => pipeline(F2)(
-  ap(map(exports.multiCurryN(2)(f))(F1))
+  ap(map(exports.curryGroupsN(2)(f))(F1))
 )
 
 

package.json

@@ -27,7 +27,7 @@
     "cov": "npx tap test/*test.js --coverage-report=lcov",
     "rebcont": "git add . && git rebase --continue",
     "toc": "npx markdown-toc DOCUMENTATION.md > toc",
-    "doc": "npx documentation build 'index.js' -f html -o auto-docs",
+    "doc": "npx documentation build 'index.js' -f html -o auto-docs --github",
     "test": "npm run ava",
     "testw": "npm run avaw"
   },

test/accum.test.js

@@ -0,0 +1,16 @@
+const test = require('./config')
+const { accum } = require('..')
+
+test('accum transforms simple reducer to accumulator', t=>{
+	const add = accum((state,v)=>state+v)(10)
+	t.is(add(1),10+1)
+	t.is(add(2),10+1+2)
+	t.is(add(-1),10+1+2-1)
+})
+
+test('accum works with reducer with variadic tuples of values', t=>{
+	const concat = accum((arr, ...rest)=>arr.concat(rest))([0])
+	t.deepEqual(concat(1),[0,1])
+	t.deepEqual(concat(),[0,1])
+	t.deepEqual(concat(1,2,3),[0,1,1,2,3])
+})

test/multiCurry2.test.js

@@ -1,10 +1,10 @@
 const test = require('./config')
-const { multiCurry2 } = require('..')
+const { curryGroups2 } = require('..')
 
-test('multiCurry2 arg function', t => {
-	t.is( multiCurry2((a,b)=>a+b)(1)(2), 3)
+test('curryGroups2 arg function', t => {
+	t.is( curryGroups2((a,b)=>a+b)(1)(2), 3)
 })
 
-test('multiCurry2 3 arg function', t => {
-  t.is( multiCurry2((a,b,c)=>a+b+c)(1,2)(3), 6)
+test('curryGroups2 3 arg function', t => {
+  t.is( curryGroups2((a,b,c)=>a+b+c)(1,2)(3), 6)
 })

test/multiCurryN.test.js

@@ -1,23 +1,23 @@
 const test = require('./config')
-const { multiCurryN } = require('..')
+const { curryGroupsN } = require('..')
 
 const add = (x,y)=>x+y
 const collect = (...args) => args
 
-test('multiCurryN(1) does not change function', t=>{
-	t.is(multiCurryN(1)(add)(11,22), 11+22)
-	t.deepEqual(multiCurryN(1)(collect)(11,22), [11,22])
+test('curryGroupsN(1) does not change function', t=>{
+	t.is(curryGroupsN(1)(add)(11,22), 11+22)
+	t.deepEqual(curryGroupsN(1)(collect)(11,22), [11,22])
 })
 
-test('multiCurryN applied to 2 groups of args', t=>{
-	t.deepEqual(multiCurryN(2)(collect)(11)(22), [11,22])
-	t.deepEqual(multiCurryN(2)(collect)(11,2)(22,3,1), [11,2,22,3,1])
+test('curryGroupsN applied to 2 groups of args', t=>{
+	t.deepEqual(curryGroupsN(2)(collect)(11)(22), [11,22])
+	t.deepEqual(curryGroupsN(2)(collect)(11,2)(22,3,1), [11,2,22,3,1])
 })
 
-test('multiCurryN applied to 3 groups of args', t=>{
-	t.deepEqual(multiCurryN(3)(collect)(11,2)(22)(3,1), [11,2,22,3,1])
+test('curryGroupsN applied to 3 groups of args', t=>{
+	t.deepEqual(curryGroupsN(3)(collect)(11,2)(22)(3,1), [11,2,22,3,1])
 })
 
-test('multiCurryN applied to 4 groups of args', t=>{
-	t.deepEqual(multiCurryN(4)(collect)(11,2)(22)(3)(1), [11,2,22,3,1])
+test('curryGroupsN applied to 4 groups of args', t=>{
+	t.deepEqual(curryGroupsN(4)(collect)(11,2)(22)(3)(1), [11,2,22,3,1])
 })