TSS/8 Algol

This document describes TSS/8 ALGOL (DECUS 8-330), which is an adaptation of 4K ALGOL (DECUS 8-213) for the TSS/8 operating system. It serves as a supplemental guide, focusing only on the differences from the original 4K ALGOL.

Key points include:

• Distribution & Loading: Distributed as a single TSS/8 SAVE format paper tape, loaded into the System Library using PIP, and called by typing *R ALGOL.
• Program Preparation: Source programs are disk files prepared using TSS/8 EDIT. Tabs in EDIT default to 8 characters but can be reduced to 3.
• Execution: It's a "compile and go" system. Users input the source file name and can specify an output file for a 4K executable binary (otherwise it compiles directly to disk). Programs are re-run using *START 400.
• Error Handling: Numerical error codes are replaced by self-explanatory messages, with line numbers corresponding to EDIT's scheme (though the line number indicates detection, not necessarily the exact error location).

• Input/Output (within program execution):

  • All input must be terminated by the RETURN key, with RUBOUT for editing.
  • Multiple values can be input on a single line, separated by commas.
  • High-speed reader/punch are unavailable; READ and WRITE commands must use device code 1.

• Language Specifics & Bugs:

  • Array variables support single or double subscripts; lower bounds must be 0 or 1, and double-subscripted arrays require equal lower bounds (e.g., [0:X,0:]).
  • Run-time errors generate "OPS n" messages; the program generally attempts to continue, but recovery is not possible if it halts.
  • The 'AND' function bug from 4K ALGOL has been fixed.
  • A known bug prevents proper compilation of multiple assignments for real variables (e.g., X=Y:=Z:=5; is treated as Y:=Z:=5;).