├── .github ├── ISSUE_TEMPLATE │ ├── discussion.md │ └── issue.md └── PULL_REQUEST_TEMPLATE.md ├── .gitignore ├── COPYING ├── CopyrightWaivers.txt ├── LICENSE ├── package.json ├── readme.md ├── tallbag.png ├── types.d.ts └── usage.md /.github/ISSUE_TEMPLATE/discussion.md: -------------------------------------------------------------------------------- 1 | --- 2 | name: Discussion 3 | about: Feel free to talk about any Tallbag-related topic! 4 | 5 | --- 6 | 7 | 8 | -------------------------------------------------------------------------------- /.github/ISSUE_TEMPLATE/issue.md: -------------------------------------------------------------------------------- 1 | --- 2 | name: Issue 3 | about: Report an inconsistency or logical hole in the Tallbag Specification 4 | 5 | --- 6 | 7 | 8 | -------------------------------------------------------------------------------- /.github/PULL_REQUEST_TEMPLATE.md: -------------------------------------------------------------------------------- 1 | 2 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | /node_modules 2 | /ignore 3 | pnpm-lock.yaml 4 | package-lock.json -------------------------------------------------------------------------------- /COPYING: -------------------------------------------------------------------------------- 1 | Creative Commons Legal Code 2 | 3 | CC0 1.0 Universal 4 | 5 | CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES NOT PROVIDE 6 | LEGAL SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT CREATE AN 7 | ATTORNEY-CLIENT RELATIONSHIP. CREATIVE COMMONS PROVIDES THIS 8 | INFORMATION ON AN "AS-IS" BASIS. CREATIVE COMMONS MAKES NO WARRANTIES 9 | REGARDING THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS 10 | PROVIDED HEREUNDER, AND DISCLAIMS LIABILITY FOR DAMAGES RESULTING FROM 11 | THE USE OF THIS DOCUMENT OR THE INFORMATION OR WORKS PROVIDED 12 | HEREUNDER. 13 | 14 | Statement of Purpose 15 | 16 | The laws of most jurisdictions throughout the world automatically confer 17 | exclusive Copyright and Related Rights (defined below) upon the creator 18 | and subsequent owner(s) (each and all, an "owner") of an original work of 19 | authorship and/or a database (each, a "Work"). 20 | 21 | Certain owners wish to permanently relinquish those rights to a Work for 22 | the purpose of contributing to a commons of creative, cultural and 23 | scientific works ("Commons") that the public can reliably and without fear 24 | of later claims of infringement build upon, modify, incorporate in other 25 | works, reuse and redistribute as freely as possible in any form whatsoever 26 | and for any purposes, including without limitation commercial purposes. 27 | These owners may contribute to the Commons to promote the ideal of a free 28 | culture and the further production of creative, cultural and scientific 29 | works, or to gain reputation or greater distribution for their Work in 30 | part through the use and efforts of others. 31 | 32 | For these and/or other purposes and motivations, and without any 33 | expectation of additional consideration or compensation, the person 34 | associating CC0 with a Work (the "Affirmer"), to the extent that he or she 35 | is an owner of Copyright and Related Rights in the Work, voluntarily 36 | elects to apply CC0 to the Work and publicly distribute the Work under its 37 | terms, with knowledge of his or her Copyright and Related Rights in the 38 | Work and the meaning and intended legal effect of CC0 on those rights. 39 | 40 | 1. Copyright and Related Rights. A Work made available under CC0 may be 41 | protected by copyright and related or neighboring rights ("Copyright and 42 | Related Rights"). Copyright and Related Rights include, but are not 43 | limited to, the following: 44 | 45 | i. the right to reproduce, adapt, distribute, perform, display, 46 | communicate, and translate a Work; 47 | ii. moral rights retained by the original author(s) and/or performer(s); 48 | iii. publicity and privacy rights pertaining to a person's image or 49 | likeness depicted in a Work; 50 | iv. rights protecting against unfair competition in regards to a Work, 51 | subject to the limitations in paragraph 4(a), below; 52 | v. rights protecting the extraction, dissemination, use and reuse of data 53 | in a Work; 54 | vi. database rights (such as those arising under Directive 96/9/EC of the 55 | European Parliament and of the Council of 11 March 1996 on the legal 56 | protection of databases, and under any national implementation 57 | thereof, including any amended or successor version of such 58 | directive); and 59 | vii. other similar, equivalent or corresponding rights throughout the 60 | world based on applicable law or treaty, and any national 61 | implementations thereof. 62 | 63 | 2. Waiver. To the greatest extent permitted by, but not in contravention 64 | of, applicable law, Affirmer hereby overtly, fully, permanently, 65 | irrevocably and unconditionally waives, abandons, and surrenders all of 66 | Affirmer's Copyright and Related Rights and associated claims and causes 67 | of action, whether now known or unknown (including existing as well as 68 | future claims and causes of action), in the Work (i) in all territories 69 | worldwide, (ii) for the maximum duration provided by applicable law or 70 | treaty (including future time extensions), (iii) in any current or future 71 | medium and for any number of copies, and (iv) for any purpose whatsoever, 72 | including without limitation commercial, advertising or promotional 73 | purposes (the "Waiver"). Affirmer makes the Waiver for the benefit of each 74 | member of the public at large and to the detriment of Affirmer's heirs and 75 | successors, fully intending that such Waiver shall not be subject to 76 | revocation, rescission, cancellation, termination, or any other legal or 77 | equitable action to disrupt the quiet enjoyment of the Work by the public 78 | as contemplated by Affirmer's express Statement of Purpose. 79 | 80 | 3. Public License Fallback. Should any part of the Waiver for any reason 81 | be judged legally invalid or ineffective under applicable law, then the 82 | Waiver shall be preserved to the maximum extent permitted taking into 83 | account Affirmer's express Statement of Purpose. In addition, to the 84 | extent the Waiver is so judged Affirmer hereby grants to each affected 85 | person a royalty-free, non transferable, non sublicensable, non exclusive, 86 | irrevocable and unconditional license to exercise Affirmer's Copyright and 87 | Related Rights in the Work (i) in all territories worldwide, (ii) for the 88 | maximum duration provided by applicable law or treaty (including future 89 | time extensions), (iii) in any current or future medium and for any number 90 | of copies, and (iv) for any purpose whatsoever, including without 91 | limitation commercial, advertising or promotional purposes (the 92 | "License"). The License shall be deemed effective as of the date CC0 was 93 | applied by Affirmer to the Work. Should any part of the License for any 94 | reason be judged legally invalid or ineffective under applicable law, such 95 | partial invalidity or ineffectiveness shall not invalidate the remainder 96 | of the License, and in such case Affirmer hereby affirms that he or she 97 | will not (i) exercise any of his or her remaining Copyright and Related 98 | Rights in the Work or (ii) assert any associated claims and causes of 99 | action with respect to the Work, in either case contrary to Affirmer's 100 | express Statement of Purpose. 101 | 102 | 4. Limitations and Disclaimers. 103 | 104 | a. No trademark or patent rights held by Affirmer are waived, abandoned, 105 | surrendered, licensed or otherwise affected by this document. 106 | b. Affirmer offers the Work as-is and makes no representations or 107 | warranties of any kind concerning the Work, express, implied, 108 | statutory or otherwise, including without limitation warranties of 109 | title, merchantability, fitness for a particular purpose, non 110 | infringement, or the absence of latent or other defects, accuracy, or 111 | the present or absence of errors, whether or not discoverable, all to 112 | the greatest extent permissible under applicable law. 113 | c. Affirmer disclaims responsibility for clearing rights of other persons 114 | that may apply to the Work or any use thereof, including without 115 | limitation any person's Copyright and Related Rights in the Work. 116 | Further, Affirmer disclaims responsibility for obtaining any necessary 117 | consents, permissions or other rights required for any use of the 118 | Work. 119 | d. Affirmer understands and acknowledges that Creative Commons is not a 120 | party to this document and has no duty or obligation with respect to 121 | this CC0 or use of the Work. -------------------------------------------------------------------------------- /CopyrightWaivers.txt: -------------------------------------------------------------------------------- 1 | Copyright Statement for Contributions to the Tallbag Standard 2 | ============================================================= 3 | 4 | I hereby represent that all present, past and future contributions I make to 5 | the Tallbag project (which is the repository at callbag/tallbag on GitHub) are 6 | governed by the Creative Commons Zero 1.0 Universal copyright statement, placing 7 | my contributions in the public domain. This entails that to the extent possible 8 | under law I waive all copyright and related or neighboring rights to the code or 9 | documents I contribute. I also represent that I have the authority to perform 10 | the above waiver with respect to the entirety of my contributions. 11 | 12 | The text of the copyright statement is included in the COPYING file at the root 13 | of the Tallbag repository at 14 | https://github.com/callbag/tallbag/blob/master/COPYING. 15 | 16 | Underwriting parties: 17 | 18 | GitHub username| Real Name, Email Address used for git, Company (optional) 19 | ---------------+---------------------------------------------------------------- 20 | staltz | Andre Medeiros, andre@staltz.com 21 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | Licensed under Public Domain (CC0) 2 | 3 | To the extent possible under law, the person who associated CC0 with 4 | this code has waived all copyright and related or neighboring 5 | rights to this code. 6 | 7 | You should have received a copy of the CC0 legalcode along with this 8 | work. If not, see . -------------------------------------------------------------------------------- /package.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "tallbag", 3 | "version": "1.2.0", 4 | "description": "Extension of the Callbag spec to add operator metadata", 5 | "repository": { 6 | "type": "git", 7 | "url": "git+https://github.com/callbag/tallbag.git" 8 | }, 9 | "main": "index.js", 10 | "types": "types.d.ts", 11 | "author": "PUBLIC", 12 | "license": "CC0", 13 | "keywords": [ 14 | "callbag", 15 | "tallbag", 16 | "callback", 17 | "standard", 18 | "spec", 19 | "observable", 20 | "iterable" 21 | ], 22 | "dependencies": { 23 | "callbag": "1.2.0" 24 | }, 25 | "devDependencies": { 26 | "ts-node": "^4.1.0", 27 | "typescript": "3.2.x" 28 | } 29 | } -------------------------------------------------------------------------------- /readme.md: -------------------------------------------------------------------------------- 1 | # Tallbag 2 | 3 | > A Callbag-compatible spec that adds introspection data 4 | 5 | ![Tallbag logo](./tallbag.png) 6 | 7 | * Functionally the same as callbags 8 | * Tallbags can interoperate with callbags, and vice-versa 9 | * Tallbags deliver **data**, but also generate **shadow callbags** which deliver **metadata** 10 | 11 | The motivation for Tallbag is to provide a mechanism for creating and delivering metadata concerning any chain of Callbag operators. Such metadata can then be used by (visual) developer tools, for instance to display a graph of the chain of operators. 12 | 13 | Because it seemed unlikely that plain callbags could support delivering metadata, a new spec was created. However, this has very few differences with Callbag, and is fully compatible with Callbag. 14 | 15 | To see an example of what tallbags can achieve, check out this [static renderer of the chain operators](https://github.com/staltz/tallbag-for-each-poc-static-graph). Different and more robust renderers could be created. 16 | 17 | **[READ HERE HOW TO USE TALLBAGS](./usage.md)** 18 | 19 | ## Summary 20 | 21 | * Upon greeting, tallbags accept a 3rd (optional) argument: a shadow callbag 22 | * Shadow callbags are regular callbag sources that deliver metadata about the chain of tallbags 23 | * Every tallbag is a callbag 24 | * Every callbag works as a tallbag (where the third greeting argument is missing) 25 | 26 | ## Specification 27 | 28 | **`(type: number, payload?: any, shadow?: Callbag) => void`** 29 | 30 | ### Definitions 31 | 32 | - *Tallbag*: a function of signature (TypeScript syntax:) `(type: 0 | 1 | 2, payload?: any) => void` 33 | - *Greet*: if a tallbag is called with `0` as the first argument, we say "the tallbag is greeted", while the code which performed the call "greets the tallbag" 34 | - *Deliver*: if a tallbag is called with `1` as the first argument, we say "the tallbag is delivered data", while the code which performed the call "delivers data to the tallbag" 35 | - *Terminate*: if a tallbag is called with `2` as the first argument, we say "the tallbag is terminated", while the code which performed the call "terminates the tallbag" 36 | - *Source*: a tallbag which is expected to deliver data 37 | - *Sink*: a tallbag which is expected to be delivered data 38 | 39 | ### Protocol 40 | 41 | The capitalized keywords used here follow [IETF's RFC 2119](https://www.ietf.org/rfc/rfc2119.txt). 42 | 43 | **Greets**: `(type: 0, cb: Tallbag, shadow?: Callbag) => void` 44 | 45 | A tallbag is *greeted* when the first argument is `0` and the second argument is another tallbag (a function). **The third argument is an optional callbag, known as the _shadow callbag_.** 46 | 47 | **Handshake** 48 | 49 | When a source is greeted and given a sink as payload, the sink MUST be greeted back with a tallbag payload that is either the source itself or another tallbag (known as the "talkback"). In other words, greets are mutual. Reciprocal greeting is called a *handshake*. 50 | 51 | **Termination**: `(type: 2, err?: any) => void` 52 | 53 | A tallbag is *terminated* when the first argument is `2` and the second argument is either undefined (signalling termination due to success) or any truthy value (signalling termination due to failure). 54 | 55 | After the handshake, the source MAY terminate the sink. Alternatively, the sink MAY terminate the source after the handshake has occurred. If the source terminates the sink, then the sink SHOULD NOT terminate the source, and vice-versa. In other words, termination SHOULD NOT be mutual. 56 | 57 | **Data delivery** `(type: 1, data: any) => void` 58 | 59 | Amount of deliveries: 60 | 61 | - A tallbag (either sink or source) MAY be delivered data, once or multiple times 62 | 63 | Window of valid deliveries: 64 | 65 | - A tallbag MUST NOT be delivered data before it has been greeted 66 | - A tallbag MUST NOT be delivered data after it has been terminated 67 | - A sink MUST NOT be delivered data after it terminates its source 68 | 69 | **Reserved codes** 70 | 71 | A tallbag SHOULD NOT be called with any of these numbers as the first argument: `3`, `4`, `5`, `6`, `7`, `8`, `9`. Those are called *reserved codes*. A tallbag MAY be called with codes other than those in the range `[0-9]`, but this specification makes no claims in those cases. 72 | 73 | ## Legal 74 | 75 | This project is offered to the Public Domain in order to allow free use by interested parties who want to create compatible implementations. For details see `COPYING` and `CopyrightWaivers.txt`. 76 | 77 |

78 | 79 | CC0 80 | 81 |
82 | To the extent possible under law, 83 | 84 | Tallbag Standard Special Interest Group 85 | has waived all copyright and related or neighboring rights to 86 | Tallbag Standard. 87 | This work is published from: 88 | Finland. 89 |

90 | -------------------------------------------------------------------------------- /tallbag.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/callbag/tallbag/3f5a5abef8946c124505efd51b20a961bba23e9f/tallbag.png -------------------------------------------------------------------------------- /types.d.ts: -------------------------------------------------------------------------------- 1 | import {Callbag} from 'callbag'; 2 | 3 | export type START = 0; 4 | export type DATA = 1; 5 | export type END = 2; 6 | export type RESERVED_3 = 3; 7 | export type RESERVED_4 = 4; 8 | export type RESERVED_5 = 5; 9 | export type RESERVED_6 = 6; 10 | export type RESERVED_7 = 7; 11 | export type RESERVED_8 = 8; 12 | export type RESERVED_9 = 9; 13 | 14 | /** 15 | * A Tallbag dynamically receives input of type I 16 | * and dynamically delivers output of type O 17 | */ 18 | export type Tallbag = { 19 | (t: START, d: Tallbag, s?: Callbag): void; 20 | (t: DATA, d: I): void; 21 | (t: END, d?: any): void; 22 | }; 23 | 24 | /** 25 | * A source only delivers data 26 | */ 27 | export type Source = Tallbag; 28 | 29 | /** 30 | * A sink only receives data 31 | */ 32 | export type Sink = Tallbag; 33 | 34 | export type SourceFactory = (...args: Array) => Source; 35 | 36 | export type SourceOperator = ( 37 | ...args: Array 38 | ) => (source: Source) => Source; 39 | 40 | /** 41 | * Conditional types for contained type retrieval 42 | */ 43 | export type UnwrapSource> = T extends Source< 44 | infer R, 45 | any 46 | > 47 | ? R 48 | : never; 49 | export type UnwrapSink> = T extends Sink 50 | ? R 51 | : never; 52 | -------------------------------------------------------------------------------- /usage.md: -------------------------------------------------------------------------------- 1 | # Usage 2 | 3 | ## How to use tallbags 4 | 5 | When running in production, tallbags are exactly the same as callbags, both in behavior and in usage. The only practical difference is that the imports may change. 6 | 7 | ```diff 8 | -const {forEach, interval, map, filter, take, pipe} = require('callbag-basics'); 9 | +const {forEach, interval, map, filter, take, pipe} = require('tallbag-basics'); 10 | 11 | pipe( 12 | interval(1000), 13 | map(x => x + 1), 14 | filter(x => x % 2), 15 | take(5), 16 | forEach(x => console.log(x)) 17 | ); 18 | ``` 19 | 20 | When running in development, tallbags produce data for developer tools, which can help you debug your code. That's how easy it is to use tallbags, if you're already familiar with callbags. 21 | 22 | ## Mixing callbags and tallbags 23 | 24 | You can also mix and match callbag libraries with tallbags libraries, in production there should be no visible difference. The code below works as you would expect: 25 | 26 | ```diff 27 | const {forEach, interval, map, take, pipe} = require('callbag-basics'); 28 | +const filter = require('tallbag-filter'); 29 | 30 | pipe( 31 | interval(1000), 32 | map(x => x + 1), 33 | + filter(x => x % 2), 34 | take(5), 35 | forEach(x => console.log(x)) 36 | ); 37 | ``` 38 | 39 | When running in development, the devtools that depend on metadata from the tallbags will be missing data for every callbag that was included. That's the only downside of mixing these two. 40 | 41 | ## How to create Tallbag libraries 42 | 43 | A shadow callbag can be (according to the Tallbag spec) any callbag, but in practice most libraries should use a default shadow implementation which collects operator chain metadata as JSON. This is what the module `shadow-callbag` is for. It comes with one utility: `makeShadow()`. 44 | 45 | When implementing a Tallbag library, it's useful to start from a Callbag library implementation, and adapt it. You could do this as fork. The implementation is slightly different for operators and for factories (creation operators). 46 | 47 | ### Source factories 48 | 49 | To add a shadow callbag to a source factory (a.k.a. creation operator): 50 | 51 | - Import/require `makeShadow` from `shadow-callbag` 52 | - In the source factory, create `const shadow = makeShadow('my-library')` 53 | - When your source greets the sink, pass the `shadow` as the 3rd argument 54 | - Whenever the source is going to deliver data to the sink, also deliver that same data to the shadow: `shadow(1, data)` 55 | 56 | See example below, where we convert `callbag-interval` to `tallbag-interval`: 57 | 58 | ```diff 59 | +const makeShadow = require('shadow-callbag').default; 60 | 61 | const interval = period => (start, sink) => { 62 | if (start !== 0) return; 63 | let i = 0; 64 | + const shadow = makeShadow('interval'); 65 | const id = setInterval(() => { 66 | + shadow(1, i); 67 | sink(1, i); 68 | i++; 69 | }, period); 70 | function talkback(t) { 71 | if (t === 2) clearInterval(id); 72 | } 73 | - sink(0, talkback); 74 | + sink(0, talkback, shadow); 75 | }; 76 | ``` 77 | 78 | ### Operators 79 | 80 | Adding a shadow callbag to an tallbag operator is similar to source factories, but this time you have to handle **two shadows**: the shadow coming from above, and the shadow to be given downwards. 81 | 82 | - Import/require `makeShadow` from `shadow-callbag` 83 | - When the source greets the operator, create `const shadow = makeShadow('my-library', shadowFromAbove)` 84 | - When the operator greets the sink, pass the `shadow` as the 3rd argument 85 | - Whenever the operator is going to deliver data to the sink, also deliver that same data to the shadow: `shadow(1, data)` 86 | 87 | In the example below, we convert `callbag-filter` to `tallbag-filter`. The shadow coming from above is `s`, and the shadow sent downwards is `shadow`. 88 | 89 | ```diff 90 | +const makeShadow = require('shadow-callbag').default; 91 | 92 | const filter = condition => source => (start, sink) => { 93 | if (start !== 0) return; 94 | let talkback; 95 | - source(0, (t, d) => { 96 | + let shadow; 97 | + source(0, (t, d, s) => { 98 | if (t === 0) { 99 | + shadow = makeShadow('filter', s); 100 | talkback = d; 101 | - sink(0, talkback); 102 | + sink(0, talkback, shadow); 103 | } else if (t === 1) { 104 | - if (condition(d)) sink(t, d); 105 | + if (condition(d)) { 106 | + shadow(t, d); 107 | + sink(t, d); 108 | + } 109 | else talkback(1); 110 | } 111 | else sink(t, d); 112 | }); 113 | }; 114 | ``` 115 | --------------------------------------------------------------------------------