libwy-0.69.6 is released https://sourceforge.net/projects/cscall/
The manpage document (description) for Spu is modifed a bit. -----------------------
Wy.Sct.Spu(3wy) Wy.Sct.Spu(= 3wy)

NAME
Spu - Class of general purpose Soft-CPU

SYNOPSIS
Except POD types, C structures, all types are declared in namespace = Wy.

#include <CSCall/Sct.h>

Spu (Soft CPU) is a revised model of Turing Machine and a class = that
acts like a general purpose CPU-based computing machine to provide =
se=E2=80=90
mantics for computing language and for remote program communication.

The main differences of Spu and general purpose CPU (or TM) is that=
Spu
has no =C2=B4register=C2=B4 nor =C2=B4flag=C2=B4, Spu has only a tap=
e. The tape is initially
empty. Every object (referred to as tape variable) in the tape is a= llo=E2=80=90
cated via instruction Alloc and identified by a continuous index num= ber.
Tape variable can be any C++ type, including Spu.

The instruction of Spu is application definable. Except necessary = few,
about >30 instructions are defined for convenience, see man= page
Wy.Sct(3wy).

Documentation following omits the scope name Wy::Sct for each occurr= ence
of Spu for clearity.

PUBLIC MEMBERS
class Reply
typedef ssize_t IndexType
Spu()
~Spu()

InstrIdx next_instr
Array<InstrIdx> istack
Array<unsign char> tape
PtrArray<InstrBase> program

template<T> T& get_data(IndexType) const
void set_instr_base()
Errno run(InstrIdx)
Errno step()
void add_instr(InstrBase*)
----[cut]

This post is to emphasize the theoretical function and capability of C/C++ language, which is equally important to their practical usage.
Many might be surprised what the hell C/C++ has anything to do with the theoretical Turing Machine (altho many discussion/program of C/C++ are/were actually abstract, therefore theoretical) and might think they don't need s= uch a
'trivial' thing. Probably, but likely naive: Turing Machine is the the mode=
l of
all general purpose computers. ALL things, including C++, are merely differ= ent
aspects of TM. The real thing is actually even more, all deterministic form=
al
logic and mathemathics (if presented in a formal way) are less powerful tha=
n TM.
C++'s application needs not to be database, html, png...,etc.

Ex1: "Object Oriented": Every function call can be viewed as a method of th=
e
object involved in the tape... (programing style involves the decompos= tion
of the problem, important, but not changing the essence)

Ex2: "Sequence point": The concept of 'sequence pint' is unnecessary in Spu
program. In C/C++, 'sequence point' has to be invented. Even so, it mi= ght
still not be the final term.

Ex3: if((ch>=3D'a')&&(ch<=3D'z')) { /* ... */ };
In Spu program, the C/C++ expression above would be like:

Jb(ch,'a',lab1); // if ch<'a', goto lab1 (exact expression may be a = bit
// different)
Ja(ch,'z',lab1); // if ch>'z', goto lab1
/* ... */
lab1: ...

No need to explain what the logical compound statement really mean (
tradition logic has the similar prboem, just more subtler).

Ex4: The Peano axiom:
1. 1=E2=88=88=E2=84=95
2. n=E2=88=88=E2=84=95 -> S(n)=E2=88=88=E2=84=95

A problem of Peano axiom is: Is infinity a natural number?
The basic answer is that, formal logic is inadequate for procedual fac=
t.
Basically, Peano axiom did not solve what the 'natural number' is, it = just
goes in circle changing termonology like C++ does (useful, though, if = you
do not dig deeper, and no deeper usage as well).

Ex5: Multi-tasking in Spu is basically just multiple instances of class Spu=
..
Or, you can make tape variables whose type is Spu...

Ex6: Traditional TM is a simplest case of Spu. It is no sense to restrict
operations to comparing symbols and only moving r/w head left or right=
to
be orthodoxical. And, the idea of Non-Deterministic TM (an obscure,
obstructive now) can be dropped.

---------
Beside the theoretical part. Class Spu is also useful as the back-end of al=
l
interpreting languages (sufificitate ones may be highly optimized).

Also because the implement of Spu is short, the range of application is hug=
e and
foundamental. Clib may consider adding one such thing.


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