Measured, compiling a DO loop left one return entry spare under
INTERPRET and a defining word called from inside another word
overflowed the nine-entry return stack (D-2); the prompt loop will take
one more.
C@ and C! shift without a loop. The code generator shifts each opcode
into the word being built, so nothing is placed by a counted shift, and
the address masks come from a table. The dictionary search, the
in-liner, the end of a loop and the making of a data word are each one
word reached by a jump.
Every kind of line now leaves at least three return entries spare while
it compiles; a word run from the interpreter has six; and CREATE ...
DOES> works from the prompt, from a word, and from a word that calls
that.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The fourth layer of the compiler capsule. compile.v4: INTERPRET's
loop, STATE [ ] : ; EXIT IMMEDIATE LITERAL COMPILE [COMPILE] ' EXECUTE,
CREATE VARIABLE CONSTANT DOES>, and IF ELSE THEN BEGIN UNTIL AGAIN
WHILE REPEAT DO ?DO LOOP +LOOP on a control-flow stack in memory.
forth.v4: the first words of the vocabulary, the in-line ones.
FORTH source now goes in and running code comes out. 49 programmes
were run through the v3 binary and through this; every result agrees,
bar COMPILE, which v3 cannot run. The code laid down for each control
structure is word for word the expansion DECOMPOSITION.md gives.
A line may have six values on the stack while it is interpreted, and
words called from the interpreter may nest eight deep.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
WORD, the dictionary words and the code generator run underneath
whatever the user has on the stacks, which are ten and nine deep (D-2).
Measured, they used five to seven data cells of their own, leaving a
line about three. Each now keeps what it works on in its file's
scratch cells and has at most three cells on the data stack; , calls
nothing; and the longest chains of calls are shorter.
The public words of core.v4, input.v4 and dict.v4 get dictionary
headers. NUMBER is split so the interpreter can have a flag instead of
NODE-ERROR. The host-node tests share one memory map, host_map.h.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The third layer of the compiler capsule, v4/capsule/codegen.v4: opcodes,
literals and branches packed into instruction words at HERE, by the
rules of sections 1.2 and 2. (OP,) (LIT,) (LABEL) (BRANCH,) (JUMP,)
(CALL,) (BRANCH>) (RESOLVE) (FLUSH) (CG-RESET).
Tested by laying the same programmes down with the text assembler on
one node and with the code generator, running, on another, and
comparing memory word for word: every opcode, literals and branches in
every slot position, and 600 random programmes. What it lays down is
then run.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The second layer of the compiler capsule, v4/capsule/dict.v4: HERE ALIGN
ALLOT , C, 2, PAD LATEST; an entry layout reached entirely from the xt,
with >LINK LFA LINK> >NAME NFA NAME> CFA PFA >BODY TRAVERSE SMUDGE
HIDDEN on it; and FIND and ' .
FIND is FORTH-79's and v3's. ' is FORTH-79's: the parameter field
address, which for a code word is what FIND gives. ALLOT counts cells
(D-1). 31 characters of a name are significant.
Executed at both cell widths against a list of 300 entries kept in C.
WORD no longer holds its length on the return stack.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Ruled 2026-10-04: standard words follow the standard where v3 did not.
EXPECT takes up to n characters (v3 took n-1) and does nothing for
n <= 0. QUERY takes up to 80 (v3: 1024). WORD stores the delimiter it
met, or a zero at the end of the text, after the word, and leaves >IN
just past that one delimiter (v3 skipped them all and stored a zero);
the word may be up to 255 characters (v3: 62).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The first layer of the compiler capsule, on the host node: TIB >IN SPAN
SOURCE BL EXPECT QUERY WORD ENCLOSE CONVERT NUMBER and the comment
words. The definitions are text, v4/capsule/core.v4 (the core words
they rest on) and v4/capsule/input.v4, assembled by the text assembler,
which can now read a file.
EXPECT, QUERY, WORD and ENCLOSE behave as v3's. CONVERT and NUMBER are
FORTH-79 (ruled 2026-10-04): any BASE, a double in the standard order,
and NUMBER returns a signed double or sets NODE-ERROR.
Executed at both cell widths against C and against values recorded from
the v3 binary.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>