Commit: b15d78daa446db7e12e7f4e7d8835ee23342a4ce Author: Randy Palamar Date: Wed, 11 Aug 2021 08:31:06 -0600 initial commit Diffstat:
| A | LICENSE | | | 15 | +++++++++++++++ |
| A | README.md | | | 93 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
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diff --git a/LICENSE b/LICENSE @@ -0,0 +1,15 @@ +ISC License (ISC) + +© 2021 Randy Palamar <palamar@ualberta.ca> + +Permission to use, copy, modify, and distribute this software for any +purpose with or without fee is hereby granted, provided that the above +copyright notice and this permission notice appear in all copies. + +THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR +ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF +OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. diff --git a/README.md b/README.md @@ -0,0 +1,93 @@ +# oboeru +A collection of simple tools for reviewing flashcards. + +Inspired by [oboeta](https://github.com/jtvaughan/oboeta). + +## Just use Anki +[Anki](https://github.com/ankitects/anki) was always a little bit +excessive but it has only gotten worse as time goes on. Here are some +key problems with it: + +* Cards are stored in a binary database. + +* Relies on tons of terrible software such as qtwebengine. + +* Build system relies on java despite there not being a single line of + java in Anki's code base. + +* Newer versions are not portable because of the terrible build system. + +* Anki's buttons for rating cards can have unintended + [consequences](https://web.archive.org/web/20201101024335if_/https://massimmersionapproach.com/table-of-contents/anki/low-key-anki/the-ease-factor-problem). + +There is really no reason for flashcards to be this complicated. + +## Solution +oboeru solves this problem by not caring about how you store your +cards. In fact all it does is maintain a ledger of card ids, their +creation date, their due date, and the number of times the card has +acted as a leech. Everything else is completely up to you. + +### What _does_ oboeru do then? +oboeru reads supplied ledgers, finds cards up for review, shuffles +them, and finally prints out the originating ledgers name and card id +separated by a tab to stdout. Then it waits for commands provided via +a named pipe. Depending on the response it will update the current card +and print the next card to stdout or rewrite the ledgers and exit. + +## Algorithm +oboeru uses an algorithm inspired by the simplicity of the +[Leitner](https://en.wikipedia.org/wiki/Leitner_system) +system but still drawing on some of the lessons of the SuperMemo +[SM-2](https://www.supermemo.com/en/archives1990-2015/english/ol/sm2) +algorithm. Specifically a card can only be passed or failed and it's +interval will always be changed by a fixed growth or shrink rate. Like +in Anki, cards can become leeches from too many failures. The relevant +code is as follows (some parts omitted): + + static void + bump_card(Card *card, int status) + { + diff = card->due - card->created; + switch (status) { + case CARD_PASS: + if (diff < MINIMUM_INCREASE) + card->due += MINIMUM_INCREASE; + else + card->due += diff * GROWTH_RATE; + break; + case CARD_FAIL: + if (diff > LEECH_AGE) + card->leeches++; + card->due += diff * SHRINK_RATE; + } + } + +Take for example a card with an interval of 6 days, `GROWTH_RATE = 1.8`, +and `SHRINK_RATE = 0.66` (simplified for readability): + + bump_card(card, CARD_PASS) + card->due = +10.8 days + bump_card(card, CARD_FAIL) + card->due = +4 days + +## Ledger Format +The format for storing the ledgers is 1 card per line with fields tab +separated. An example follows: + + # id created due leeches extra + 23 2021年07月09日16時18分 2021年08月09日05時01分 3 全て + 0099 2021年07月09日14時18分 2021年08月11日14時19分 0 飲み込む + +The time formatting is configurable via `config.h`. The extra field +can be used for whatever, for example to check for duplicates. It can +contain any character besides `\0` and `\n`. + +## Installation +Modify `config.h` and `config.mk` to your liking and use the following +to install (using root as needed): + + make clean install + +## Example Usage +_coming soon_