refactor(transducers): replace wrapBoth/Left/Right w/ wrap()

- deprecate existing wrap*() iters - update docs & readme
thi-ng · May 14, 2018 · e238541 · e238541
1 parent fbba5d2
commit e238541
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diff --git a/packages/transducers/README.md b/packages/transducers/README.md
@@ -813,11 +813,7 @@ itself. Returns nothing.
 
 #### `vals<T>(x: IObjectOf<T>): IterableIterator<T>`
 
-#### `wrapBoth<T>(src: T[], n?: number): IterableIterator<T>`
-
-#### `wrapLeft<T>(src: T[], n?: number): IterableIterator<T>`
-
-#### `wrapRight<T>(src: T[], n?: number): IterableIterator<T>`
+#### `wrap<T>(src: T[], n = 1, left = true, right = true): IterableIterator<T>`
 
 ## Authors
 

diff --git a/packages/transducers/src/index.ts b/packages/transducers/src/index.ts
@@ -124,6 +124,4 @@ export * from "./iter/repeatedly";
 export * from "./iter/reverse";
 export * from "./iter/tuples";
 export * from "./iter/vals";
-export * from "./iter/wrap-both";
-export * from "./iter/wrap-left";
-export * from "./iter/wrap-right";
+export * from "./iter/wrap";
diff --git a/packages/transducers/src/iter/wrap-both.ts b/packages/transducers/src/iter/wrap-both.ts
@@ -1,21 +1,12 @@
-import { illegalArgs } from "@thi.ng/errors/illegal-arguments";
+import { wrap } from "./wrap";
 
 /**
- * Combination of `wrapLeft()` and `wrapRight()`. Yields iterator of
- * `src` with the last `n` values of `src` prepended at the beginning
- * and the first `n` values appended at the end. Throws error if `n` < 0
- * or larger than `src.length`.
+ * See `wrap()`.
  *
+ * @deprecated superceded by `wrap()`
  * @param src
  * @param n
  */
-export function* wrapBoth<T>(src: T[], n = 1) {
-    (n < 0 || n > src.length) && illegalArgs(`wrong number of wrap items: got ${n} max: ${src.length}`);
-    for (let m = src.length, i = m - n; i < m; i++) {
-        yield src[i];
-    }
-    yield* src;
-    for (let i = 0; i < n; i++) {
-        yield src[i];
-    }
+export function wrapBoth<T>(src: T[], n = 1) {
+    return wrap(src, n);
 }
diff --git a/packages/transducers/src/iter/wrap-left.ts b/packages/transducers/src/iter/wrap-left.ts
@@ -1,17 +1,12 @@
-import { illegalArgs } from "@thi.ng/errors/illegal-arguments";
+import { wrap } from "./wrap";
 
 /**
- * Yields iterator of `src` with the last `n` values of `src` prepended
- * at the beginning. Throws error if `n` < 0 or larger than
- * `src.length`.
+ * See `wrap()`.
  *
+ * @deprecated superceded by `wrap()`
  * @param src
  * @param n
  */
-export function* wrapLeft<T>(src: T[], n = 1) {
-    (n < 0 || n > src.length) && illegalArgs(`wrong number of wrap items: got ${n} max: ${src.length}`);
-    for (let m = src.length, i = m - n; i < m; i++) {
-        yield src[i];
-    }
-    yield* src;
+export function wrapLeft<T>(src: T[], n = 1) {
+    return wrap(src, n, true, false);
 }
diff --git a/packages/transducers/src/iter/wrap-right.ts b/packages/transducers/src/iter/wrap-right.ts
@@ -1,16 +1,12 @@
-import { illegalArgs } from "@thi.ng/errors/illegal-arguments";
+import { wrap } from "./wrap";
 
 /**
- * Yields iterator of `src` with the first `n` values of `src` appended
- * at the end. Throws error if `n` < 0 or larger than `src.length`.
+ * See `wrap()`.
  *
+ * @deprecated superceded by `wrap()`
  * @param src
  * @param n
  */
-export function* wrapRight<T>(src: T[], n = 1) {
-    (n < 0 || n > src.length) && illegalArgs(`wrong number of wrap items: got ${n} max: ${src.length}`);
-    yield* src;
-    for (let i = 0; i < n; i++) {
-        yield src[i];
-    }
+export function wrapRight<T>(src: T[], n = 1) {
+    return wrap(src, n, false, true);
 }
diff --git a/packages/transducers/src/iter/wrap.ts b/packages/transducers/src/iter/wrap.ts
@@ -0,0 +1,27 @@
+import { illegalArgs } from "@thi.ng/errors/illegal-arguments";
+
+/**
+ * Yields iterator of `src` with the last `n` values of `src` prepended
+ * at the beginning (if `left` is truthy) and/or the first `n` values
+ * appended at the end (if `right` is truthy). Wraps both sides by
+ * default and throws error if `n` < 0 or larger than `src.length`.
+ *
+ * @param src
+ * @param n
+ * @param left
+ * @param right
+ */
+export function* wrap<T>(src: T[], n = 1, left = true, right = true) {
+    (n < 0 || n > src.length) && illegalArgs(`wrong number of wrap items: got ${n} max: ${src.length}`);
+    if (left) {
+        for (let m = src.length, i = m - n; i < m; i++) {
+            yield src[i];
+        }
+    }
+    yield* src;
+    if (right) {
+        for (let i = 0; i < n; i++) {
+            yield src[i];
+        }
+    }
+}