K is a rewrite-based executable semantic framework in which programming languages, type systems, and formal analysis tools can be defined using configurations, computations, and rules. Configurations organize the state in units called cells, which are labeled and can be nested. Computations carry computational meaning as special nested list structures sequentializing computational tasks, such as fragments of program. Computations extend the original language abstract syntax. K (rewrite) rules make it explicit which parts of the term they read-only, write-only, read-write, or do not care about. This makes K suitable for defining truly concurrent languages even in the presence of sharing. Computations are like any other term in a rewriting environment: they can be matched, moved from one place to another, modified, or deleted. This makes K suitable for defining control-intensive features such as abrupt termination, exceptions, or call/cc.

This distribution contains a tool prototype which implements many of K's features. For more on the K framework and how to use the current tool, go to k/tutorial (start with the README file there), or refer to the website, which contains video tutorials, at http://www.kframework.org/.

NOTE: This README file contains information regarding the stable release of the K tool indicated in the title above, regardless of whether it came with the release itself or with subsequent nightly/latest builds. This file is updated only when new stable versions are officially released.

WARNING: The command line options for kompile, krun, kast and ktest have recently changed! Type --help with any of these to see the new options, or see CHANGELOG.md for more details.

For a list of high-level changes since the previous release, please refer to the file CHANGELOG.md in the current directory.

See src/README.md