Dear SWI-Prolog user, SWI-Prolog 10.1.7 is ready for download. This release lands the long-running overhaul of Unicode handling — both in the source-language syntax and in the editor/terminal rendering — together with a handful of behaviour changes to align with the Unicode recommendations for…

[image] anon37422618: So that Emoijs don’t need string quoting most of the time Emoji are now solo. This means they do not needs quotes unless you have multiple adjacent, e.g., ?- atom_concat(🩶, 🩶, X). X = '🩶🩶'. The idea is that most Unicode symbols have a semantics on their own and just …

Those are true concerns. As is, we accept P* and S* as solos. There is also a derived property called Pattern Syntax. That is a stable subset of P* and S*. The downside is that it has been frozen in 2005 and lacks several currency symbols, a lot of arrows, the emoticons, etc. I don’t know. …

[image] anon37422618: Well there is a PRIVATE_USE category covering U+E000–U+F8FF, U+F0000–U+FFFFD and U+100000–U+10FFFD for example. I am currently mapping it to “invalid”, similar like UNASSIGNED I think private use and “unstable” are different things. And yes, also for SWI-Prolog priva…

[image] anon37422618: Well some encoding requires pairs. Like UTF-16. A pair then exists on the physical level of the encoding, you might not see it on the logical level of the encoding. SWI-Prolog deals with encoding at I/O. After the I/O, everything is a sequence of Unicode code points …

[image] anon37422618: It is allowed in Java Java is older than UTF-16 (not by much) and probably imagined the now obsolete UCS-2 encoding as what the world would look like. Javascript and Windows fell into the same trap. [image] anon37422618: I think its there because Java wants to be a…

[image] anon37422618: /* SWI-Prolog 10.1.7, Windows 11 Console */ ?- compare(C, '𝄞', '豈'). C = (<). This mostly confirms my view on UTF-16, which we use for compatibility with the C API on Windows. This is of course a bug as the result must be > as it is on non-Windows. Unicode started wi…

Ann: SWI-Prolog 10.1.7

Releases

alanbur May 18, 2026, 1:37pm 17

See BUG: internal error in GUI debugger - #2 by alanbur

Topic		Replies	Views
Ann: SWI-Prolog 10.1.8 Releases	4	216	June 15, 2026
Unicode symbols, and a possible numerical paradox! Discussion	27	2428	June 27, 2022
Trouble with Unicode Help!	10	470	September 21, 2021
Ann: SWI-Prolog 9.0.4 (stable) Releases	2	664	May 3, 2023
Ann: SWI-Prolog 10.1.6 Releases	7	226	April 27, 2026

Ann: SWI-Prolog 10.1.7

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