CSNOBOL4 2.3.3 — the C implementation of SNOBOL4, originally by Philip L. Budne, maintained here by the snobol4ever project as the base for the SCRIP language family.

CSNOBOL4 is a free, faithful port of the original Bell Labs SNOBOL4 implementation. It is derived directly from v311.sil — the SIL (SNOBOL4 Implementation Language) macro source — with C as the target language. The result is a complete, standard- conforming SNOBOL4 interpreter including:

• Full pattern matching with backtracking
• Dynamic typing and garbage collection
• User-defined data types (DATA)
• On-the-fly compilation (CODE, EVAL)
• The complete standard function library

Upstream home: http://www.regressive.org/snobol4/csnobol4
Original author: Philip L. Budne
License: BSD 2-Clause (see COPYRIGHT)

This fork tracks upstream 2.3.3 and adds:

See FENCE.md for the full design and implementation notes.

./configure
make

Requires: C compiler, make. No bison or flex needed (generated files are committed).

Tested on: Linux x86-64, macOS.

# Quick smoke test
echo "OUTPUT = 'hello world'" | ./snobol4

The snobol4ever/x64 repo contains SPITBOL x64, the primary correctness oracle for all pattern matching behavior. When in doubt, SPITBOL is right.

v311.sil          SIL source — the canonical reference implementation
snobol4.c         Main interpreter (generated + hand-edited)
isnobol4.c        Instrumented interpreter variant
data.c / data.h   Static data tables (generated from v311.sil)
data_init.c       Runtime data initialization
syn.c / syn.h     Syntax tables
test/             Test suite
doc/              Documentation
FENCE.md          Design notes for FENCE(P) implementation

Copyright © 1993–2021 Philip L. Budne. BSD 2-Clause License — see COPYRIGHT.
snobol4ever modifications: same license.