An educational pure functional programming library in TypeScript
Tighten traverser FP purity, consolidate Exit namespace, clean redundant typeclass comments, and bump dev dependencies
+61
-71
+15
-15
bun.lock
+15
-15
bun.lock
···
5
5
"": {
6
6
"name": "purus-ts",
7
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"devDependencies": {
8
-
"@biomejs/biome": "^2.3.12",
9
-
"@types/bun": "^1.1.0",
10
-
"typescript": "^5",
8
+
"@biomejs/biome": "^2.4.12",
9
+
"@types/bun": "^1.3.12",
10
+
"typescript": "^6.0.3",
11
11
},
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12
},
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},
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"packages": {
15
-
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20
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"@biomejs/cli-linux-arm64": ["@biomejs/cli-linux-arm64@2.3.12", "", { "os": "linux", "cpu": "arm64" }, "sha512-nbOsuQROa3DLla5vvsTZg+T5WVPGi9/vYxETm9BOuLHBJN3oWQIg3MIkE2OfL18df1ZtNkqXkH6Yg9mdTPem7A=="],
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"@biomejs/cli-linux-arm64-musl": ["@biomejs/cli-linux-arm64-musl@2.4.12", "", { "os": "linux", "cpu": "arm64" }, "sha512-FhfpkAAlKL6kwvcVap0Hgp4AhZmtd3YImg0kK1jd7C/aSoh4SfsB2f++yG1rU0lr8Y5MCFJrcSkmssiL9Xnnig=="],
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"@biomejs/cli-linux-x64-musl": ["@biomejs/cli-linux-x64-musl@2.3.12", "", { "os": "linux", "cpu": "x64" }, "sha512-kVGWtupRRsOjvw47YFkk5mLiAdpCPMWBo1jOwAzh+juDpUb2sWarIp+iq+CPL1Wt0LLZnYtP7hH5kD6fskcxmg=="],
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"@biomejs/cli-linux-x64-musl": ["@biomejs/cli-linux-x64-musl@2.4.12", "", { "os": "linux", "cpu": "x64" }, "sha512-dwTIgZrGutzhkQCuvHynCkyW6hJxUuyZqKKO0YNfaS2GUoRO+tOvxXZqZB6SkWAOdfZTzwaw8IEdUnIkHKHoew=="],
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"@biomejs/cli-win32-arm64": ["@biomejs/cli-win32-arm64@2.4.12", "", { "os": "win32", "cpu": "arm64" }, "sha512-B0DLnx0vA9ya/3v7XyCaP+/lCpnbWbMOfUFFve+xb5OxyYvdHaS55YsSddr228Y+JAFk58agCuZTsqNiw2a6ig=="],
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"@biomejs/cli-win32-x64": ["@biomejs/cli-win32-x64@2.3.12", "", { "os": "win32", "cpu": "x64" }, "sha512-qqGVWqNNek0KikwPZlOIoxtXgsNGsX+rgdEzgw82Re8nF02W+E2WokaQhpF5TdBh/D/RQ3TLppH+otp6ztN0lw=="],
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"@biomejs/cli-win32-x64": ["@biomejs/cli-win32-x64@2.4.12", "", { "os": "win32", "cpu": "x64" }, "sha512-yMckRzTyZ83hkk8iDFWswqSdU8tvZxspJKnYNh7JZr/zhZNOlzH13k4ecboU6MurKExCe2HUkH75pGI/O2JwGA=="],
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-
"@types/bun": ["@types/bun@1.3.4", "", { "dependencies": { "bun-types": "1.3.4" } }, "sha512-EEPTKXHP+zKGPkhRLv+HI0UEX8/o+65hqARxLy8Ov5rIxMBPNTjeZww00CIihrIQGEQBYg+0roO5qOnS/7boGA=="],
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+
"@types/bun": ["@types/bun@1.3.12", "", { "dependencies": { "bun-types": "1.3.12" } }, "sha512-DBv81elK+/VSwXHDlnH3Qduw+KxkTIWi7TXkAeh24zpi5l0B2kUg9Ga3tb4nJaPcOFswflgi/yAvMVBPrxMB+A=="],
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"@types/node": ["@types/node@24.10.1", "", { "dependencies": { "undici-types": "~7.16.0" } }, "sha512-GNWcUTRBgIRJD5zj+Tq0fKOJ5XZajIiBroOF0yvj2bSU1WvNdYS/dn9UxwsujGW4JX06dnHyjV2y9rRaybH0iQ=="],
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-
"bun-types": ["bun-types@1.3.4", "", { "dependencies": { "@types/node": "*" } }, "sha512-5ua817+BZPZOlNaRgGBpZJOSAQ9RQ17pkwPD0yR7CfJg+r8DgIILByFifDTa+IPDDxzf5VNhtNlcKqFzDgJvlQ=="],
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+
"bun-types": ["bun-types@1.3.12", "", { "dependencies": { "@types/node": "*" } }, "sha512-HqOLj5PoFajAQciOMRiIZGNoKxDJSr6qigAttOX40vJuSp6DN/CxWp9s3C1Xwm4oH7ybueITwiaOcWXoYVoRkA=="],
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-
"typescript": ["typescript@5.9.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw=="],
39
+
"typescript": ["typescript@6.0.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-y2TvuxSZPDyQakkFRPZHKFm+KKVqIisdg9/CZwm9ftvKXLP8NRWj38/ODjNbr43SsoXqNuAisEf1GdCxqWcdBw=="],
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"undici-types": ["undici-types@7.16.0", "", {}, "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw=="],
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}
+6
-6
docs-site/src/content/docs/examples/http-client.md
+6
-6
docs-site/src/content/docs/examples/http-client.md
···
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// HOW IT WORKS:
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// 1. async() takes a "register" function
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// 2. The register function receives a "resume" callback
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-
// 3. You start your async work and call resume(Exit.succeed(value)) or resume(Exit.fail(error))
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// 3. You start your async work and call resume(Exit.success(value)) or resume(Exit.failure(error))
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// 4. Return a cleanup function - it runs on cancellation
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//
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// GOTCHA: The AbortController abort() must happen in the cleanup function.
···
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.then((response) =>
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!response.ok
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? response.status === 404
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? resume(Exit.fail(HttpError.notFound(url)))
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: resume(Exit.fail(HttpError.serverError(response.status)))
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? resume(Exit.failure(HttpError.notFound(url)))
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: resume(Exit.failure(HttpError.serverError(response.status)))
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: response.json().then((data: unknown) =>
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// Use type guard instead of casting - validates at runtime
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isUser(data)
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? resume(Exit.succeed(data))
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: resume(Exit.fail(HttpError.serverError(500))),
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? resume(Exit.success(data))
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: resume(Exit.failure(HttpError.serverError(500))),
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),
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)
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.catch((err) => {
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// GOTCHA: Don't resume on AbortError - the fiber is already cancelled
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// Resuming after cancellation would cause undefined behavior
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if (err.name === "AbortError") return
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resume(Exit.fail(HttpError.network(err.message)))
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resume(Exit.failure(HttpError.network(err.message)))
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})
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// THE KEY INSIGHT: This cleanup function runs automatically on timeout/interrupt
+2
-2
docs-site/src/content/docs/examples/task-queue.md
+2
-2
docs-site/src/content/docs/examples/task-queue.md
···
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// 30% chance of failure for demo purposes
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if (Math.random() < 0.3) {
403
-
resume(Exit.fail(JobError.transient(job.id, "transient error")))
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resume(Exit.failure(JobError.transient(job.id, "transient error")))
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} else {
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resume(Exit.succeed(undefined))
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resume(Exit.success(undefined))
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}
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}, delay)
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+1
-1
docs-site/src/content/docs/tutorial/02-your-first-effect.md
+1
-1
docs-site/src/content/docs/tutorial/02-your-first-effect.md
···
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import { async, Exit } from "purus-ts"
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const delay = (ms: number) => async<void, never>(resume => {
175
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const id = setTimeout(() => resume(Exit.succeed(undefined)), ms)
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+
const id = setTimeout(() => resume(Exit.success(undefined)), ms)
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return () => clearTimeout(id) // Cleanup function
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})
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```
+3
-3
docs-site/src/content/docs/tutorial/08-concurrency-with-fibers.md
+3
-3
docs-site/src/content/docs/tutorial/08-concurrency-with-fibers.md
···
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const cancellableDelay = (ms: number) =>
226
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async<void, never>(resume => {
227
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const id = setTimeout(
228
-
() => resume(Exit.succeed(undefined)),
228
+
() => resume(Exit.success(undefined)),
229
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ms
230
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)
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···
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const controller = new AbortController()
248
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fetch(url, { signal: controller.signal })
250
-
.then(response => resume(Exit.succeed(response)))
250
+
.then(response => resume(Exit.success(response)))
251
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.catch(error => {
252
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if (error.name !== "AbortError") {
253
-
resume(Exit.fail(error))
253
+
resume(Exit.failure(error))
254
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}
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// Don't resume on AbortError - fiber is already done
256
256
})
+1
-1
docs-site/src/content/docs/tutorial/10-building-a-complete-app.md
+1
-1
docs-site/src/content/docs/tutorial/10-building-a-complete-app.md
+6
-6
examples/http-client/with-purus.ts
+6
-6
examples/http-client/with-purus.ts
···
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// HOW IT WORKS:
91
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// 1. async() takes a "register" function
92
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// 2. The register function receives a "resume" callback
93
-
// 3. You start your async work and call resume(Exit.succeed(value)) or resume(Exit.fail(error))
93
+
// 3. You start your async work and call resume(Exit.success(value)) or resume(Exit.failure(error))
94
94
// 4. Return a cleanup function - it runs on cancellation
95
95
//
96
96
// GOTCHA: The AbortController abort() must happen in the cleanup function.
···
108
108
.then((response) =>
109
109
!response.ok
110
110
? response.status === 404
111
-
? resume(Exit.fail(HttpError.notFound(url)))
112
-
: resume(Exit.fail(HttpError.serverError(response.status)))
111
+
? resume(Exit.failure(HttpError.notFound(url)))
112
+
: resume(Exit.failure(HttpError.serverError(response.status)))
113
113
: response.json().then((data: unknown) =>
114
114
// Use type guard instead of casting - validates at runtime
115
115
isUser(data)
116
-
? resume(Exit.succeed(data))
117
-
: resume(Exit.fail(HttpError.serverError(500))),
116
+
? resume(Exit.success(data))
117
+
: resume(Exit.failure(HttpError.serverError(500))),
118
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),
119
119
)
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.catch((err) => {
121
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// GOTCHA: Don't resume on AbortError - the fiber is already cancelled
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// Resuming after cancellation would cause undefined behavior
123
123
if (err.name === "AbortError") return
124
-
resume(Exit.fail(HttpError.network(err.message)))
124
+
resume(Exit.failure(HttpError.network(err.message)))
125
125
})
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// THE KEY INSIGHT: This cleanup function runs automatically on timeout/interrupt
+2
-2
examples/task-queue/with-purus.ts
+2
-2
examples/task-queue/with-purus.ts
···
156
156
157
157
// 30% chance of failure for demo purposes
158
158
if (Math.random() < 0.3) {
159
-
resume(Exit.fail(JobError.transient(job.id, "transient error")))
159
+
resume(Exit.failure(JobError.transient(job.id, "transient error")))
160
160
} else {
161
-
resume(Exit.succeed(undefined))
161
+
resume(Exit.success(undefined))
162
162
}
163
163
}, delay)
164
164
+3
-3
package.json
+3
-3
package.json
+1
-4
src/effect/exit.ts
+1
-4
src/effect/exit.ts
···
77
77
? failure(onFailure(exit.error))
78
78
: interrupted(exit.by)
79
79
80
-
// Namespace for convenient access (using original naming convention)
80
+
// Namespace for convenient dotted access to the Exit API.
81
81
export const Exit = {
82
-
succeed: success,
83
-
fail: failure,
84
-
interrupt: interrupted,
85
82
success,
86
83
failure,
87
84
interrupted,
+9
-9
src/prelude/option.ts
+9
-9
src/prelude/option.ts
···
188
188
*/
189
189
export const traverseOption =
190
190
<A, B>(f: (a: A) => Option<B>) =>
191
-
(as: readonly A[]): Option<readonly B[]> => {
192
-
const results: B[] = []
193
-
for (const a of as) {
194
-
const o = f(a)
195
-
if (o._tag === "None") return none
196
-
results.push(o.value)
197
-
}
198
-
return some(results)
199
-
}
191
+
(as: readonly A[]): Option<readonly B[]> =>
192
+
as.reduce<Option<readonly B[]>>(
193
+
(acc, a) =>
194
+
acc._tag === "None"
195
+
? acc
196
+
: ((o: Option<B>): Option<readonly B[]> =>
197
+
o._tag === "None" ? none : some([...acc.value, o.value]))(f(a)),
198
+
some([]),
199
+
)
200
200
201
201
/**
202
202
* Collapse an array of Options into an Option of an array.
+9
-9
src/prelude/result.ts
+9
-9
src/prelude/result.ts
···
252
252
*/
253
253
export const traverseResult =
254
254
<A, B, E>(f: (a: A) => Result<B, E>) =>
255
-
(as: readonly A[]): Result<readonly B[], E> => {
256
-
const results: B[] = []
257
-
for (const a of as) {
258
-
const r = f(a)
259
-
if (r._tag === "Err") return r
260
-
results.push(r.value)
261
-
}
262
-
return ok(results)
263
-
}
255
+
(as: readonly A[]): Result<readonly B[], E> =>
256
+
as.reduce<Result<readonly B[], E>>(
257
+
(acc, a) =>
258
+
acc._tag === "Err"
259
+
? acc
260
+
: ((r: Result<B, E>): Result<readonly B[], E> =>
261
+
r._tag === "Err" ? r : ok([...acc.value, r.value]))(f(a)),
262
+
ok([]),
263
+
)
264
264
265
265
/**
266
266
* Collapse an array of Results into a Result of an array.
+3
-10
src/prelude/typeclasses.ts
+3
-10
src/prelude/typeclasses.ts
···
27
27
* @module prelude/typeclasses
28
28
*/
29
29
30
-
import { flatMapOption, mapOption, type Option, some } from "./option"
30
+
import { flatMapOption, mapOption, none, type Option, some } from "./option"
31
31
import { bimap, chainResult, mapResult, ok, type Result } from "./result"
32
32
33
33
// -----------------------------------------------------------------------------
34
-
// Type Class Interfaces (Educational)
35
-
// -----------------------------------------------------------------------------
36
-
37
-
// -----------------------------------------------------------------------------
38
34
// Conceptual Type Class Interfaces
39
35
// -----------------------------------------------------------------------------
40
-
// TypeScript lacks higher-kinded types (HKT), so we cannot express these
41
-
// interfaces generically like "interface Functor<F[_]>". Instead, we document
42
-
// the pattern conceptually. The instance objects below show concrete examples.
43
36
44
37
/**
45
38
* Functor - types that can be mapped over.
···
179
172
<B>(of_: Option<(a: A) => B>): Option<B> =>
180
173
of_._tag === "Some" && oa._tag === "Some"
181
174
? some(of_.value(oa.value))
182
-
: { _tag: "None" }
175
+
: none
183
176
184
177
// -----------------------------------------------------------------------------
185
178
// Instance Objects (Demonstrating the Pattern)
···
264
257
(oa: Option<A>, ob: Option<B>): Option<C> =>
265
258
oa._tag === "Some" && ob._tag === "Some"
266
259
? some(f(oa.value, ob.value))
267
-
: { _tag: "None" }
260
+
: none