08142: Strange filter results and sort order in the machine list

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
08142	Interface	Minor	Always	Nov 28, 2021, 10:04	Dec 2, 2021, 14:13

Tester	MilanSK	View Status	Public	Platform	MAME (Official Binary)
Assigned To		Resolution	No change required	OS	Windows Vista/7/8 (64-bit)
Status [?]	Closed			Driver
Version	0.238	Fixed in Version		Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	08142: Strange filter results and sort order in the machine list
Description	In the main window, when I start typing, search is activated. I would expect the list displays only machines matching the typed string. Instead, various machines are displayed, obviously not matching the typed string. Additionally, they are sorted in weird order.
Steps To Reproduce	1. Install fresh official MAME 0.238 release. 2. Start typing "didaktik gama 89".
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems

Attached Files	filtering_and_sort_order.png (177,940 bytes) Nov 28, 2021, 10:04 Uploaded by MilanSK Machine list filtered to "didaktik gama 89"

No.19502 hap Developer Nov 28, 2021, 11:02	The list is from best match to worst match, not in alphabetical order. mp68a and Mikrodator are in it because the company is "Didact AB" MAME's search is not very good (see related bugreport on searching for "Magic Sword" for example), but this specific search case you reported is not that bad.
No.19503 MilanSK Tester Nov 28, 2021, 12:18	Would it make sense to add an option for exact match? Perhaps to implement this type of search (and applying alphabetical sort order on the result) could be a very easy task.
No.19511 cuavas Administrator Nov 29, 2021, 03:04	It will always favour an exact match over an inexact match. Even with a different search algorithm, sorting the results alphabetically wouldn’t make sense. Consider what would happen with a search like “nes” – this will match the short name for Nintendo Entertainment System/Famicom perfectly, but it’s also be a perfect partial match for a very large number of systems because it’s a commonly occurring sequence of letters (e.g. it matches “oneshot”, the short name for One Shot One Kill, with a relatively low edit distance). Sorting alphabetically when there are a very large pool of items being searched from tends to put irrelevant results higher. The search algorithm used to look for exact substring matches. However, besides being very slow, it didn’t work well at all. Searching for “nes” or “neo geo” wouldn’t return anything even close to what the user wanted. The main issue with using edit distance for searching is that some descriptions have huge amounts of disambiguation text in them which causes “magic sword” to have a lower edit distance to “Magic Card (set 1)” than it has to “Magic Sword: Heroic Fantasy (World 900725)” – “sword” and “card” both have “rd” in them, and all the additional stuff at the end of the full description of Magic Sword drives the edit distance up.
No.19514 B2K24 Senior Tester Dec 1, 2021, 18:11	Seems like there's nothing to change here as the way it currently functions has been explained. Someone else can reopen if there's a productive purpose to it. Closing as no change required.
No.19519 Tafoid Administrator Dec 2, 2021, 14:13	https://github.com/mamedev/mame/pull/8924 is up for evaluation