From 0ec712a97061eda49c426c72d8e344a744026658 Mon Sep 17 00:00:00 2001
From: Kovachev <86124720+KovachevBot@users.noreply.github.com>
Date: Mon, 29 May 2023 16:21:29 +0100
Subject: [PATCH] Create README.md

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+# Japanese yomi removal script
+This script is intended to traverse the tracking template/category https://en.wiktionary.org/wiki/Special:WhatLinksHere/Template:tracking/ja-pron/yomi on the English Wiktionary.
+We recently removed the `yomi` (alias: `y`) parameter from the pronunciation template {{ja-pron}}, so this script is intended to remove all occurrences of this
+now-deprecated and unnecessary parameter from entries in this category.
+
+## Method of operation
+The script iterates over all the entries in this category, then performs a simple substitution to get rid of the yomis for each occurrence of
+{{ja-pron}}.
+The regular expression that does this is: `({{ja-pron(?:\|[^\|]+?=[^\|]+?|\|[^\|]+)*?)\|(?:y|yomi)=(?:o|on|go|goon|ko|kan|kanon|so|soon|to|toon|ky|kanyo|kanyoon|k|kun|j|ju|y|yu|i|irr|irreg|irregular)((?:\|[^\|]+?=[^\|]+?|\|[^\|]+)*}})`
+You will see two capturing groups, one before the "yomi" portion, and one after; given that these two together comprise the entire template and its arguments,
+except for the yomi argument, we simply replace any match for this pattern with the two matching groups concatenated together,
+e.g. if we have `{{ja-pron|しょう|y=kan|acc=0}}`, the match would contain the two subgroups  `{{ja-pron|しょう` and `|acc=0}}`, so when we put them
+together, we get `{{ja-pron|しょう|acc=0}}`, and in this way the yomi is removed.
+
+## Method to guarantee no malfunction
+Although I believe the script to have no flaws, it is natural for an unforeseen bug to potentially occur, especially with a complicated regex
+like this. The safeguard I have is to check the page text before and after editing: we expect all the {{ja-pron}}s to stay in the same order
+that they were originally, since my script doesn't change the fundamental arrangement of the page, but with each one having one less argument
+(determinable by counting the number of |s) than it did before the edit. We assert this every single time an edit is made, so that if this invariant
+is somehow broken, and an error must have occurred somewhere, the program will halt immediately and before making the edit at all.