README.md
In rswipl: Embed 'SWI'-'Prolog'

SWI-Prolog binding to library utf8proc

This package wraps the utf8proc library, providing up-to-date inspection and transformation of Unicode strings and atoms. It is the foundation for SWI-Prolog's normalisation forms (NFC, NFD, NFKC, NFKD), case folding, grapheme-cluster iteration (UAX#29), and per-code-point property lookup (general category, bidi class, display width, combining class, case mappings, ...). The public Prolog API is exported from library(unicode); see the predicates unicode_nfc/2, unicode_property/2, atom_graphemes/2, and friends for details.

A second library, library(unicode_security), ships the UTS #39 security helpers (confusable skeleton, mixed-script resolution, identifier restriction levels) and UAX #24 script properties. Its tables are derived from the Unicode Character Database files under data/ by etc/gen_uts39.pl; the generated uts39_data.{c,h} is checked in. After a UCD version bump, refresh both with ninja regen-uts39 in the build directory.

This is a git submodule of the main swi-prolog/swipl-devel repository. It builds only when the system has libutf8proc installed (available in every major package manager); the upstream utf8proc source is no longer vendored. Issues and pull requests specific to this binding belong here; Unicode-data bugs should be reported upstream at the utf8proc tracker.