A high level Unicode text processing library.

This project is based on VSS (Virtual String System). VSS has been split into two projects:

• vss-text (this project): a library for Unicode text processing.
• vss-extra: libraries for handling JSON, Regexp, XML and other features based on vss-text.

Significant changes are planned in vss-text with the goal to make it a high-quality, high-performance library suitable for a wide range of applications.

The changes include the following (non-exhaustive list):

• API Changes
  • Introduce an immutable string type.
  • Repurpose the mutable Virtual_String type to a string builder type.
  • Possibly rename the root package VSS to a new more appropriate name. GPR project and repository names might change accordingly.
• (done) Drop the support of multiple internal encodings in favor of a single internal encoding (likely UTF-8) for improved performance.

The objectives of this project are

• To introduce a definite type that represents a string of Unicode characters and provides a handy set of operations.
• The API should be encoding independent and allows efficient implementations.
• Besides separating string API from in-memory data representation, it should separate string API from input/output stream representation.
• To provide a clear, well-defined semantic for iteration over string elements, such as unicode unit, grapheme cluster, etc.
• To avoid string element integer indexes, because this isn't necessarily constant time and could mislead about indexed element kind.
• To prefer safe results over raising exceptions where possible.

Warning: This is experimental work in progress, everything is subject to change.

Note: Some Ada 2022 features are used in source code. This requires compiler that supports them.

Prefered way to install is to download sources and run

make all install PREFIX=/path/to/install

Or you can use Alire library manager:

alr get --build vss_text

Then you can use it as dependency in the project file:

with "vss_text.gpr";

• API Reference
• Tips & Tricks

@AdaCore.

Feel free to dive in! Open an issue or submit PRs.

Apache License v2.0 with LLVM Exceptions.