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=(o.o)=  ~byakuren  =(o.o)=
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Flowlog Documentation (flowlog.c)

This documentation set covers Flowlog: a single-file, single-process ISO-style Prolog system built from flowlog.c and using pthreads for parallelism.

Flowlog provides three execution engines:

• wamvm (default) — a bytecode VM for compiled clause bodies (still sharing the same unifier and built-ins as wam). It can fall back to wam when a program/query uses unsupported features (or be forced to error via FLOWLOG_WAMVM_REQUIRE_VM=1). In VM-only mode, it passes the INRIA ISO suite.
• wam — a WAM-lite engine for fast execution of most ISO-style code (including dynamic database and call-by-variant tabling). It can fall back to the interpreter when required.
• interp / tree — a direct interpreter (“tree-walking”) used as the reference/fallback engine.

What you get

• A self-contained Prolog runtime (flowlog.c) you can compile with any reasonably POSIX C toolchain.
• ISO-style behavior for core language features (terms, control, arithmetic, database, streams).
• An interactive REPL with history and line editing (TTY only).
• Multicore OR-parallelism by default, plus conservative AND-parallelism when supported (see PARALLELISM.md).

Start here

• QUICKSTART.md — build, run, and first query
• CLI.md — command-line + REPL reference
• USER_GUIDE.md — writing and running programs (portable ISO style)
• PARALLELISM.md — parallel flags, safety notes, tuning
• CONFORMANCE.md — conformance goals and test suites
• PREDICATES.md — built-in predicates, evaluables, and Flowlog extensions
• TESTS.md — regression tests and ISO suite runners (full source bundle)
• BENCHMARKS.md — benchmark harnesses and reference programs (full source bundle)

Developer docs

• TECHNICAL_DETAILS.md — runtime model, memory/threads/signals, portability notes
• IMPLEMENTATION.md — parser, terms, unification, indexing, tabling, OR/AND-par internals
• DEVELOPMENT.md — building, testing, debugging, and contributing
• TROUBLESHOOTING.md — common issues (stacks, threading, performance)