@thi.ng/transducers - npm Package Compare versions

Comparing version 0.11.2 to 1.0.0

index.d.ts

@@ -12,2 +12,3 @@ export * from "./api";
 export * from "./rfn/count";
+export * from "./rfn/every";
 export * from "./rfn/frequencies";
@@ -17,3 +18,2 @@ export * from "./rfn/group-binary";
 export * from "./rfn/group-by-obj";
-export * from "./rfn/join";
 export * from "./rfn/last";
@@ -29,2 +29,4 @@ export * from "./rfn/max-compare";
 export * from "./rfn/reductions";
+export * from "./rfn/some";
+export * from "./rfn/str";
 export * from "./xform/base64";
@@ -50,2 +52,3 @@ export * from "./xform/benchmark";
 export * from "./xform/keep";
+export * from "./xform/labeled";
 export * from "./xform/map-indexed";
@@ -57,2 +60,5 @@ export * from "./xform/map-keys";
 export * from "./xform/moving-average";
+export * from "./xform/multiplex";
+export * from "./xform/multiplex-obj";
+export * from "./xform/noop";
 export * from "./xform/pad-last";
@@ -78,2 +84,4 @@ export * from "./xform/partition-by";
 export * from "./xform/throttle";
+export * from "./xform/throttle-time";
+export * from "./xform/utf8";
 export * from "./func/binary-search";
@@ -80,0 +88,0 @@ export * from "./func/comp";

index.js

@@ -17,2 +17,3 @@ "use strict";
 __export(require("./rfn/count"));
+__export(require("./rfn/every"));
 __export(require("./rfn/frequencies"));
@@ -22,3 +23,2 @@ __export(require("./rfn/group-binary"));
 __export(require("./rfn/group-by-obj"));
-__export(require("./rfn/join"));
 __export(require("./rfn/last"));
@@ -34,2 +34,4 @@ __export(require("./rfn/max-compare"));
 __export(require("./rfn/reductions"));
+__export(require("./rfn/some"));
+__export(require("./rfn/str"));
 __export(require("./xform/base64"));
@@ -55,2 +57,3 @@ __export(require("./xform/benchmark"));
 __export(require("./xform/keep"));
+__export(require("./xform/labeled"));
 __export(require("./xform/map-indexed"));
@@ -62,2 +65,5 @@ __export(require("./xform/map-keys"));
 __export(require("./xform/moving-average"));
+__export(require("./xform/multiplex"));
+__export(require("./xform/multiplex-obj"));
+__export(require("./xform/noop"));
 __export(require("./xform/pad-last"));
@@ -83,2 +89,4 @@ __export(require("./xform/partition-by"));
 __export(require("./xform/throttle"));
+__export(require("./xform/throttle-time"));
+__export(require("./xform/utf8"));
 __export(require("./func/binary-search"));
@@ -85,0 +93,0 @@ __export(require("./func/comp"));

iter/reverse.d.ts

@@ -10,2 +10,2 @@ /**
  */
-export declare function reverse<T>(input: Iterable<T>): IterableIterator<any>;
+export declare function reverse<T>(input: Iterable<T>): IterableIterator<T>;

package.json

 {
     "name": "@thi.ng/transducers",
-    "version": "0.11.2",
+    "version": "1.0.0",
     "description": "Lightweight transducer implementations for ES6 / TypeScript",
     "main": "./index.js",
     "typings": "./index.d.ts",
-    "repository": "https://github.com/thi-ng/transducers",
+    "repository": "https://github.com/thi-ng/umbrella",
     "author": "Karsten Schmidt <[e-mail]>",
@@ -14,3 +14,3 @@ "license": "Apache-2.0",
         "clean": "rm -rf *.js *.d.ts build doc func iter rfn xform",
-        "pub": "yarn run build && (cd build && yarn publish --access public)"
+        "pub": "yarn run build && yarn publish --access public"
     },
@@ -27,4 +27,3 @@ "devDependencies": {
     "dependencies": {
-        "@thi.ng/api": "^1.2.1",
-        "@thi.ng/checks": "^1.1.1"
+        "@thi.ng/api": "^1.3.0"
     },
@@ -31,0 +30,0 @@ "keywords": [

README.md

@@ -21,4 +21,4 @@ # @thi.ng/transducers
 
-Currently, the library provides altogether 75+ transducers, reducers and
-sequence generators for composing data transformation pipelines.
+This library provides altogether ~85 transducers, reducers and sequence
+generators (iterators) for composing data transformation pipelines.
 
@@ -28,16 +28,16 @@ The overall concept and many of the core functions offered here are directly
 implementation does differ (also in contrast to some other JS based
-implementations) and several less common, but generally highly useful operators
+implementations) and dozens of less common, but generally highly useful operators
 have been added, with at least a couple dozen more to come.
 
-Please see the [@thi.ng/iterators](https://github.com/thi-ng/umbrella/tree/master/packages/iterators) &
-[@thi.ng/csp](https://github.com/thi-ng/umbrella/tree/master/packages/csp) partner modules for related
-functionality, supplementing features of this library. However, this lib has no
-dependencies on either of them. The only dependency is
-[@thi.ng/api](https://github.com/thi-ng/umbrella/tree/master/packages/api) for re-using common types &
-interfaces.
+Please see the
+[@thi.ng/rstream](https://github.com/thi-ng/umbrella/tree/master/packages/rstream)
+& [@thi.ng/csp](https://github.com/thi-ng/umbrella/tree/master/packages/csp)
+partner modules for related functionality, supplementing features of this
+library and depending on it.
 
-Having said this, since 0.8.0 this project largely supersedes the
-[@thi.ng/iterators](https://github.com/thi-ng/umbrella/tree/master/packages/iterators) library for most use
-cases and offers are more powerful API and potentially faster execution of
-composed transformations (due to lack of ES generator overheads).
+Since 0.8.0 this project largely supersedes the
+[@thi.ng/iterators](https://github.com/thi-ng/umbrella/tree/master/packages/iterators)
+library for most use cases and offers are more powerful API and potentially
+faster execution of composed transformations (due to lack of ES generator
+overheads).
 
@@ -89,4 +89,4 @@ ## Installation
 // single step execution
-// (currently doesn't work w/ mapcat(), duplicate() and some others)
 // returns undefined if transducer returned no result for this input
+// returns array if transducer step produced multiple results
 f = tx.step(xform);
@@ -97,10 +97,7 @@ f(1) // 3
 f(4) // undefined
-f(5) // 15
-f(4) // undefined
-f(3) // undefined
-f(2) // undefined
-f(1) // undefined
+
+f = tx.step(take)
 ```
 
-### Histogram generation
+### Histogram generation & result grouping
 
@@ -116,4 +113,56 @@ ```typescript
 // Map { 1 => 3, 2 => 1, 3 => 1, 4 => 2 }
+
+// with optional key function, here to bin by word length
+tx.reduce(
+    tx.frequencies(x => x.length),
+    "my camel is collapsing and needs some water".split(" ")
+)
+// Map { 2 => 2, 5 => 3, 10 => 1, 3 => 1, 4 => 1 }
+
+// actual grouping
+tx.reduce(
+    tx.groupByMap(x => x.length),
+    "my camel is collapsing and needs some water".split(" ")
+)
+// Map {
+//   2 => [ 'my', 'is' ],
+//   3 => [ 'and' ],
+//   4 => [ 'some' ],
+//   5 => [ 'camel', 'needs', 'water' ],
+//   10 => [ 'collapsing' ]
+// }
 ```
 
+### Multiplexing / parallel transducer application
+
+`multiplex` and `multiplexObj` can be used to transform values in parallel
+using the provided transducers (which can be composed as usual) and results in
+a tuple or keyed object.
+
+```typescript
+tx.transduce(
+    tx.multiplex(
+        tx.map(x => x.charAt(0)),
+        tx.map(x => x.toUpperCase()),
+        tx.map(x => x.length)
+    ),
+    tx.push(),
+    ["Alice", "Bob", "Charlie"]
+)
+// [ [ "A", "ALICE", 5 ], [ "B", "BOB", 3 ], [ "C", "CHARLIE", 7 ] ]
+
+tx.transduce(
+    tx.multiplexObj({
+        initial: tx.map(x => x.charAt(0)),
+        name: tx.map(x => x.toUpperCase()),
+        len: tx.map(x => x.length)
+    }),
+    tx.push(),
+    ["Alice", "Bob", "Charlie"]
+)
+// [ { len: 5, name: 'ALICE', initial: 'A' },
+//   { len: 3, name: 'BOB', initial: 'B' },
+//   { len: 7, name: 'CHARLIE', initial: 'C' } ]
+```
+
 ### Moving average using sliding window
@@ -123,4 +172,2 @@
 // use nested reduce to compute window averages
-// this combined transducer is also directly
-// available as: `tx.movingAverage(n)`
 tx.transduce(
@@ -135,2 +182,10 @@ tx.comp(
 // [ 2.6, 3.4, 4, 4.6, 5.4, 6.2, 6.8, 7.6, 8.4 ]
+
+// this combined transducer is also directly
+// available as: `tx.movingAverage(n)`
+tx.transduce(
+    tx.movingAverage(5),
+    [1, 2, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10]
+);
+// [ 2.6, 3.4, 4, 4.6, 5.4, 6.2, 6.8, 7.6, 8.4 ]
 ```
@@ -182,3 +237,3 @@
 The `struct` transducer is simply a composition of: `partitionOf -> partition -> rename -> mapKeys`.
-[See code here](https://github.com/thi-ng/transducers/blob/master/src/xform/struct.ts).
+[See code here](https://github.com/thi-ng/umbrella/tree/master/packages/transducers/src/xform/struct.ts).
 
@@ -266,3 +321,3 @@ ```typescript
 This is a higher-order transducer, purely composed from other transducers.
-[See code here](https://github.com/thi-ng/transducers/blob/master/src/xform/hex-dump.ts).
+[See code here](https://github.com/thi-ng/umbrella/tree/master/packages/transducers/src/xform/hex-dump.ts).
 
@@ -302,3 +357,3 @@ ```typescript
 
-### Base64 en/decoding
+### Base64 & UTF-8 en/decoding
 
@@ -313,3 +368,3 @@ ```typescript
     ),
-    tx.join(),
+    tx.str(),
     tx.range(-8, 8)
@@ -328,2 +383,12 @@ );
 // [ -8, -7, -6, -5, -4, -3, -2, -1 ]
+
+buf = tx.transduce(
+    tx.comp(tx.utf8Encode(), tx.base64Encode()),
+    tx.str(),
+    "beer (🍺) or hot beverage (☕︎)"
+);
+// "YmVlciAo8J+Nuikgb3IgaG90IGJldmVyYWdlICjimJXvuI4p"
+
+tx.transduce(tx.comp(tx.base64Decode(), tx.utf8Decode()), tx.str(), buf)
+// "beer (🍺) or hot beverage (☕︎)"
 ```
@@ -344,4 +409,4 @@
 _Documentation is slowly forthcoming in the form of doc comments (incl. code
-examples) for a small, but growing number the functions listed below. Please
-see source code for now._
+examples) for a growing number the functions listed below. Please see source
+code for now._
 
@@ -392,4 +457,4 @@ ### Types
 
-Currently `partition`, `partitionBy`, `streamSort`, `streamShuffle` are the only operators making
-use of the 1-arity completing function of their reducer.
+`partition`, `partitionBy`, `streamSort`, `streamShuffle` are (examples of)
+transducers making use of their 1-arity completing function.
 
@@ -471,7 +536,8 @@ #### Reduced
 
-Helper function to build reducers.
+Helper function to compose reducers.
 
 #### `iterator<A, B>(tx: Transducer<A, B>, xs: Iterable<A>): IterableIterator<B>`
 
-Similar to `transduce()`, but emits results as ES6 iterator (and hence doesn't use a reduction function).
+Similar to `transduce()`, but emits results as ES6 iterator (and hence doesn't
+use a reduction function).
 
@@ -531,2 +597,4 @@ #### `reduce<A, B>(rfn: Reducer<A, B>, acc: A, xs: Iterable<B>): A`
 
+#### `labeled<L, T>(id: L): Transducer<T, [L, T]>`
+
 #### `map<A, B>(fn: (x: A) => B): Transducer<A, B>`
@@ -544,2 +612,8 @@
 
+#### `multiplex<T, A, B>(a: Transducer<T, A>, b: Transducer<T, B>...): Transducer<T, [A, B...]>`
+
+#### `multiplexObj<A, B>(xforms: IObjectOf<Transducer<A, any>>, rfn?: Reducer<B, [PropertyKey, any]>): Transducer<A, B>`
+
+#### `noop<T>(): Transducer<T, T>`
+
 #### `padLast<T>(n: number, fill: T): Transducer<T, T>`
@@ -585,2 +659,8 @@
 
+#### `throttleTime<T>(delay: number): Transducer<T, T>`
+
+#### `utf8Decode(): Transducer<number, string>`
+
+#### `utf8Encode(): Transducer<string, number>`
+
 ### Reducers
@@ -598,4 +678,6 @@
 
-#### `frequencies<T>(): Reducer<Map<T, number>, T>`
+#### `every<T>(pred?: Predicate<T>): Reducer<boolean, T>`
 
+#### `frequencies<A, B>(key: (x: A) => B): Reducer<Map<B, number>, A>`
+
 #### `groupBinary<T>(bits: number, key: (x: T) => number, branch?: () => IObjectOf<T[]>, leaf?: Reducer<any, T>, left?: PropertyKey, right?: PropertyKey): Reducer<any, T>`
@@ -625,2 +707,6 @@
 
+#### `reductions<A, B>(rfn: Reducer<A, B>): Reducer<A[], B>`
+
+#### `some<T>(pred?: Predicate<T>): Reducer<boolean, T>`
+
 ### Generators / Iterators
@@ -627,0 +713,0 @@

rfn/frequencies.d.ts

 import { Reducer } from "../api";
-export declare function frequencies<T>(): Reducer<Map<T, number>, T>;
+export declare function frequencies<A, B>(key?: ((x: A) => B)): Reducer<Map<B, number>, A>;

rfn/frequencies.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
-function frequencies() {
-    return [
-        () => new Map(),
-        (acc) => acc,
-        (acc, x) => acc.set(x, acc.has(x) ? acc.get(x) + 1 : 1)
-    ];
+const identity_1 = require("../func/identity");
+const count_1 = require("./count");
+const group_by_map_1 = require("./group-by-map");
+function frequencies(key = identity_1.identity) {
+    return group_by_map_1.groupByMap(key, count_1.count());
 }
 exports.frequencies = frequencies;

rfn/group-binary.d.ts

 import { IObjectOf } from "@thi.ng/api/api";
 import { Reducer } from "../api";
 /**
- * Creates a bottom-up binary tree of desired depth and choice of
- * data structures. Any value can be indexed, as long as a numeric
- * representation (key) can be obtained. This mapping is produced
+ * Creates a bottom-up, unbalanced binary tree of desired depth and
+ * choice of data structures. Any value can be indexed, as long as a
+ * numeric representation (key) can be obtained. This mapping is produced
  * by the supplied `key` function. IMPORTANT: the returned values
@@ -8,0 +8,0 @@ * MUST be unsigned and less than the provided bit length (i.e. 2^`bits`).

rfn/group-binary.js

@@ -9,5 +9,5 @@ "use strict";
 /**
- * Creates a bottom-up binary tree of desired depth and choice of
- * data structures. Any value can be indexed, as long as a numeric
- * representation (key) can be obtained. This mapping is produced
+ * Creates a bottom-up, unbalanced binary tree of desired depth and
+ * choice of data structures. Any value can be indexed, as long as a
+ * numeric representation (key) can be obtained. This mapping is produced
  * by the supplied `key` function. IMPORTANT: the returned values
@@ -14,0 +14,0 @@ * MUST be unsigned and less than the provided bit length (i.e. 2^`bits`).

rfn/group-by-map.d.ts

 import { Reducer } from "../api";
-export declare function groupByMap<A, B, C>(key: (x: A) => B, rfn?: Reducer<C, A>): Reducer<Map<B, C>, A>;
+export declare function groupByMap<A, B, C>(key?: ((x: A) => B), rfn?: Reducer<C, A>): Reducer<Map<B, C>, A>;

rfn/group-by-map.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
+const identity_1 = require("../func/identity");
 const push_1 = require("./push");
-function groupByMap(key, rfn = push_1.push()) {
+function groupByMap(key = identity_1.identity, rfn = push_1.push()) {
     return [
@@ -6,0 +7,0 @@ () => new Map(),

rfn/reductions.js

@@ -11,3 +11,3 @@ "use strict";
             if (reduced_1.isReduced(res)) {
-                acc.push(reduced_1.unreduced(res));
+                acc.push(res.deref());
                 return reduced_1.reduced(acc);
@@ -14,0 +14,0 @@ }

step.d.ts

 import { Transducer } from "./api";
-export declare function step<A, B>(tx: Transducer<A, B>): (x: A) => B;
+/**
+ * Single-step transducer execution wrapper.
+ * Returns array if transducer produces multiple results
+ * and undefined if there was no output. Else returns single
+ * result value.
+ *
+ * Likewise, once a transducer has produced a final / reduced
+ * value, all further invocations of the stepper function will
+ * return undefined.
+ *
+ * ```
+ * // single result
+ * step(map(x => x * 10))(1);
+ * // 10
+ *
+ * // multiple results
+ * step(mapcat(x => [x, x + 1, x + 2]))(1)
+ * // [ 1, 2, 3 ]
+ *
+ * // no result
+ * f = step(filter(even))
+ * f(1); // undefined
+ * f(2); // 2
+ *
+ * // reduced value termination
+ * f = step(take(2));
+ * f(1); // 1
+ * f(1); // 1
+ * f(1); // undefined
+ * f(1); // undefined
+ * ```
+ *
+ * @param tx
+ */
+export declare function step<A, B>(tx: Transducer<A, B>): (x: A) => B | B[];

step.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
-const last_1 = require("./rfn/last");
+const push_1 = require("./rfn/push");
+const index_1 = require("./index");
+/**
+ * Single-step transducer execution wrapper.
+ * Returns array if transducer produces multiple results
+ * and undefined if there was no output. Else returns single
+ * result value.
+ *
+ * Likewise, once a transducer has produced a final / reduced
+ * value, all further invocations of the stepper function will
+ * return undefined.
+ *
+ * ```
+ * // single result
+ * step(map(x => x * 10))(1);
+ * // 10
+ *
+ * // multiple results
+ * step(mapcat(x => [x, x + 1, x + 2]))(1)
+ * // [ 1, 2, 3 ]
+ *
+ * // no result
+ * f = step(filter(even))
+ * f(1); // undefined
+ * f(2); // 2
+ *
+ * // reduced value termination
+ * f = step(take(2));
+ * f(1); // 1
+ * f(1); // 1
+ * f(1); // undefined
+ * f(1); // undefined
+ * ```
+ *
+ * @param tx
+ */
 function step(tx) {
-    const rfn = tx(last_1.last())[2];
-    return (x) => rfn(undefined, x);
+    const [_, complete, reduce] = tx(push_1.push());
+    _;
+    let done = false;
+    return (x) => {
+        if (!done) {
+            let acc = reduce([], x);
+            done = index_1.isReduced(acc);
+            if (done) {
+                acc = complete(acc.deref());
+            }
+            return acc.length === 1 ?
+                acc[0] :
+                acc.length > 0 ?
+                    acc :
+                    undefined;
+        }
+    };
 }
 exports.step = step;

test/index.js

@@ -1,2 +0,2 @@
-const tx = require("../build");
+const tx = require("../");
 
@@ -15,3 +15,3 @@ console.log(
 
-    tx.transduce(tx.bits(), tx.push(), [0xaa])
+    tx.reduce(tx.every(tx.even), tx.range(10))
 );

xform/cat.d.ts

 import { Transducer } from "../api";
-export declare function cat<T>(): Transducer<T[], T>;
+export declare function cat<T>(): Transducer<Iterable<T>, T>;

xform/delayed.d.ts

 import { Transducer } from "../api";
+/**
+ * Yields transducer which wraps incoming values in promises, which
+ * resolve after specified delay time (in ms).
+ *
+ * **Only to be used in async contexts and NOT with `transduce` directly.**
+ *
+ * @param t
+ */
 export declare function delayed<T>(t: number): Transducer<T, Promise<T>>;

xform/delayed.js

@@ -5,2 +5,10 @@ "use strict";
 const delay_1 = require("../func/delay");
+/**
+ * Yields transducer which wraps incoming values in promises, which
+ * resolve after specified delay time (in ms).
+ *
+ * **Only to be used in async contexts and NOT with `transduce` directly.**
+ *
+ * @param t
+ */
 function delayed(t) {
@@ -7,0 +15,0 @@ return map_1.map((x) => delay_1.delay(x, t));

xform/drop-nth.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
-const comp_1 = require("../func/comp");
+const throttle_1 = require("./throttle");
 function dropNth(n) {
-    n--;
-    return (rfn) => {
-        const r = rfn[2];
+    n = Math.max(0, n - 1);
+    return throttle_1.throttle(() => {
         let skip = n;
-        return comp_1.compR(rfn, (acc, x) => skip-- > 0 ? r(acc, x) : (skip = n, acc));
-    };
+        return () => skip-- > 0 ? true : (skip = n, false);
+    });
 }
 exports.dropNth = dropNth;

xform/scan.d.ts

 import { Reducer, Transducer } from "../api";
-export declare function scan<A, B>(inner: Reducer<B, A>, acc?: B): Transducer<A, B>;
+export declare function scan<A, B>([initi, completei, reducei]: Reducer<B, A>): Transducer<A, B>;

xform/scan.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
-const comp_1 = require("../func/comp");
 const reduced_1 = require("../reduced");
-function scan(inner, acc) {
-    return (outer) => {
-        acc = acc || inner[0]();
-        const ri = inner[2], ro = outer[2];
-        return comp_1.compR(outer, (_acc, x) => {
-            acc = ri(acc, x);
-            if (reduced_1.isReduced(acc)) {
-                return reduced_1.ensureReduced(ro(_acc, acc.deref()));
+function scan([initi, completei, reducei]) {
+    return ([inito, completeo, reduceo]) => {
+        let acc = initi();
+        return [
+            inito,
+            (_acc) => {
+                let a = completei(acc);
+                if (a !== acc) {
+                    _acc = reduced_1.unreduced(reduceo(_acc, a));
+                }
+                acc = a;
+                return completeo(_acc);
+            },
+            (_acc, x) => {
+                acc = reducei(acc, x);
+                if (reduced_1.isReduced(acc)) {
+                    return reduced_1.ensureReduced(reduceo(_acc, acc.deref()));
+                }
+                return reduceo(_acc, acc);
             }
-            return ro(_acc, acc);
-        });
+        ];
     };
 }
 exports.scan = scan;

xform/take-nth.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
-const comp_1 = require("../func/comp");
+const throttle_1 = require("./throttle");
 function takeNth(n) {
-    n--;
-    return (rfn) => {
-        const r = rfn[2];
+    n = Math.max(0, n - 1);
+    return throttle_1.throttle(() => {
         let skip = 0;
-        return comp_1.compR(rfn, (acc, x) => {
-            if (skip === 0) {
-                skip = n;
-                return r(acc, x);
-            }
-            skip--;
-            return acc;
-        });
-    };
+        return () => (skip === 0 ? (skip = n, true) : (skip--, false));
+    });
 }
 exports.takeNth = takeNth;

xform/throttle.d.ts

@@ -0,2 +1,18 @@
+import { StatefulPredicate } from "@thi.ng/api/api";
 import { Transducer } from "../api";
-export declare function throttle<T>(delay: number): Transducer<T, T>;
+/**
+ * Similar to `filter`, but works with possibly stateful predicates
+ * to achieve rate limiting capabilities. Emits only values when
+ * predicate returns a truthy value.
+ *
+ * To support multiple instances of stateful predicates, the predicate
+ * itself must be wrapped in a no-arg function, which is called when
+ * the transducer initializes. Any stateful initialization of the
+ * predicate MUST be done in this function and the function MUST
+ * return a 1-arg function, the actual predicate applied to each value.
+ *
+ * Also see: `throttleTime()`.
+ *
+ * @param pred
+ */
+export declare function throttle<T>(pred: StatefulPredicate<T>): Transducer<T, T>;

xform/throttle.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
 const comp_1 = require("../func/comp");
-function throttle(delay) {
+/**
+ * Similar to `filter`, but works with possibly stateful predicates
+ * to achieve rate limiting capabilities. Emits only values when
+ * predicate returns a truthy value.
+ *
+ * To support multiple instances of stateful predicates, the predicate
+ * itself must be wrapped in a no-arg function, which is called when
+ * the transducer initializes. Any stateful initialization of the
+ * predicate MUST be done in this function and the function MUST
+ * return a 1-arg function, the actual predicate applied to each value.
+ *
+ * Also see: `throttleTime()`.
+ *
+ * @param pred
+ */
+function throttle(pred) {
     return (rfn) => {
         const r = rfn[2];
-        let last = 0;
-        return comp_1.compR(rfn, (acc, x) => {
-            const t = Date.now();
-            if (t - last >= delay) {
-                last = t;
-                acc = r(acc, x);
-            }
-            return acc;
-        });
+        const _pred = pred();
+        return comp_1.compR(rfn, (acc, x) => _pred(x) ? r(acc, x) : acc);
     };
 }
 exports.throttle = throttle;

New alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

No repository

Supply chain risk

Package does not have a linked source code repository. Without this field, a package will have no reference to the location of the source code use to generate the package.

Found 1 instance in 1 package

Fixed alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

No repository

Supply chain risk

Package does not have a linked source code repository. Without this field, a package will have no reference to the location of the source code use to generate the package.

Found 1 instance in 1 package

No v1

Quality

Package is not semver >=1. This means it is not stable and does not support ^ ranges.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

135832

increased by16.39%

Dependency count

1

decreased by-50%

Number of package files

217

increased by8.5%

Lines of code

2913

increased by16.61%

Number of low quality alerts

1

decreased by-50%

Number of lines in readme file

719

increased by13.59%

Dependency changes

• - [e-mail]/checks@^1.1.1

• [e-mail]/api@^1.3.0