ismael-vc/merlin

Varvara/Uxn Concatenated Interpretive Uxntal JIT Assembler REPL.

Merlin OS — Version 0.e (18M06)

Varavara's Uxntal Operating System

Memory is organized as follows:

0000   0100       @heap         @heap-ptr       @syms-ptr      fc00         ffff
|      |          |             ^               ^         @syms|@buffs         |
v ZPpt v          v             |               |              v @input @ptr   v
+--^---+----------+-------------*---------------*--------------+-v------^------+
| <ZP> | <kernel> | <user code> | <free memory> | <syms table> | | <input buf> |
+--*---+----------+-------------*---------------*--------------+-+------*------+
|==>   |##########|=============>               <==============|#|======>
 (256B)                        ( growth direction )                   (1Kb)

Operator Interaction

       Merlin CLI REPL
   █▄  Version 0.8 (06/06/2024).
 ▐ █ ▌ Concatenated Interpretive Uxntal JIT Assembler.
  ▀█   ©MMXXIV Ismael Venegas Castelló, MIT License.
       57865 bytes free (bytecode: 0, symbols: 1331 bytes used).

uxn> #2a18 DEO
*
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn> @star #2a18 DEO JMP2r

WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn> star
*
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn>

Under the Hood

A parent label starts assembly mode, this will do the following:

1. Assemble the input buffer and place the code after the current position of @here, and update the @here pointer.
2. Add an entry to the "dictionary" ("header" format still under design) and update it's pointer.

Note: [ and ] allow multiline input.

uxn> @star ( -- ) [
...   [ LIT2 "* -Console/write ] DEO
...   JMP2r
... ]

WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn> star
*
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn>

Doubts:

• star JSI semantics (but not syntax) will need to be adapted to jump to an absolute address in REPL mode?
• How to allow multiline input without using [ ]?

@here

The assembled code area will be concatenated as if assembling Uxntal normally.

| @here ( 1337 )
| a0 2a 18 17 6c  ( #2a18 DEO JMP2r )
|
∨ @here ( 133c )

@dict

The dictionary will grow in the contrary direction at a constant size for each entry. Instead of a linked list in tipycal Threaded Interpretive Languages (TILs), concatenating in inverse order to an array. When searching for a routine searching from last entry to first as done by TILs is accomplished by starting the search from the "physical beginning" of the array, where the current @dict pointer points to.

∧ @dict ( ????-n entry bytes )
|
| identifier                           addr
| s  t  a  r  ( pad to n max bytes )   1337
| 73 74 61 72 00 00 00 00 00 00 00 00  13 37
| @dict ( ???? )
| ( primitives )

ANSI Control Codes

Feature	Code
bold	1
Secondary color	2
Itallic	3
Underline	4
Blinking	5
Inverted background	7
Hidden	8
Striked through	9

Support

Environment	1	2	3	4	5	7	8	9
Windows 11 (22631.3880) Windows Terminal (1.20.11781.0) WSL2 (2.2.4.0) Ubuntu (22.04.4 LTS) dash (0.5.11+git20210903+057cd650a4ed-3build1)	✔️	✔️	✔️	✔️	✔️	✔️	✔️	✔️
Windows 11 (22631.3880) Chrome Browser (126.0.6478.182) Developer Tools	❌	❌	✔️	✔️	❌	✔️	❌	✔️

Reasoning

Concatenating instead of threading the routines allows for the usage of Uxntal and not another Uxntal like language with new or different syntax though some semantics may need to be adapted.

uxn> [
...   @<pdec> ( dec* -- )
...     DUP #64 DIV <pnum>/try
...     DUP #0a DIV <pnum>/try
...     ( >> )
...
...   @<pnum> ( num* -- )
...     #0a MOD [ LIT "0 ] ADD .Console/write DEO
...     JMP2r
...
...     &try ( num* -- )
...       DUP ?<pnum>
...       POP JMP2r
... ]

WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn> #002a <pdec>
42
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

uxn>

In this case calling <pdec> would fall through to <pnum> body as in normal Uxntal, something that would not be possible with a tipical threaded implementation.

Drifblim VS drifloon

Zero Page

• Drifblim uses Console and File, drifloon only Console.
• loon uses @token $2 while blim uses @token $1 buf $30.

on-init

• loon uses <assemble> and <read>.
• blim uses only <assemble> on files.

TODO

• Return to repl when when evaluating break BRK expression, by pressing Enter 3 times.
• #foo! should be a Number error (fixed in drifblim).
• Fix key routine.
• Reinstate include rune.
• Refactor into something better the file hierarchy.
• Implement log level.
• Fix lambda syms, not being the same as with uxnasm.
• Implement library path. (not possible due to sandbox)
• Make rom smaller (no unused space in between code/data).
• Make multiline more robust.
• Reset symbols and heap after expression evaluation.
• Fix memory usage.
• Add print strings with underscore as spaces routine.
• Clear heap and symbols after error.
• Reset PC after absolute padding expression.
• Keep trak of ZP pointer.
• Check memory limits ZP, input buffer, head and tail, before writing.
• Log session.
• Make multiline more robust with rlwrap.
• Use walkcomment and allow nesting.
• Make pmem take the lenght to dump.
• Make symbols store code length.
• Implement macros.
• Make logging toggleable.
• [], {}, () parse these correctly. (take strings into account.)
• Comment out debugging for release.
• Remove uneeded experiments.
• Integrate disassembler.
• Restore stacks without :! when aborting from all errors!
• Fix: abort early.

փ [140e]> snathoue
ERROR: Unknown reference: snathoue in expression.
ERROR: Aborting...
INFO: Assembled expression in 3 bytes.
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

փ [140e]> #23434
ERROR: Number #23434 in expression.
ERROR: Number #23434 in expression.
ERROR: Aborting...
INFO: Assembled expression in 1 bytes.
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

• Show length of padding as well:

փ [13fc]> @foo $1
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

փ [13fd]> @bar #01 ,foo STR JMP2r
Assembled bar in 6 bytes.
WST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<
RST 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|<

• print own symbols
• Enable switching in and out of evaluation/caching modes when typing an expression or including a file.
• DUP LIT 28 NEQ ?{ #00 ,&comment STR POP BRK }this_is_valid_uxntal!!!!
• shouldn't be allowed (leading / creates invalid definition):

@/MOD ( a b -- a/b a%b ) [
  DIVk STHk MUL SUB STHr SWP JMP2r
]
  ok

Rom Visualization

Repository Tree

.
|
├── bak
├── bin
├── build.sh
├── config
│   ├── buffers.tal
│   ├── constants.tal
│   ├── data.tal
│   ├── macros.tal
│   ├── options.tal
│   ├── routines.tal
│   ├── startup.tal
│   └── symbols.tal
├── doc
├── etc
├── lib
│   ├── audio
│   │   └── routines.tal
│   ├── console
│   │   └── macros.tal
│   ├── constants.tal
│   ├── control
│   │   └── routines.tal
│   ├── datetime
│   │   └── routines.tal
│   ├── file
│   │   └── routines.tal
│   ├── macros.tal
│   ├── memory
│   │   └── routines.tal
│   ├── mouse
│   │   └── routines.tal
│   ├── ops
│   │   └── macros.tal
│   ├── routines.tal
│   ├── screen
│   │   ├── data.tal
│   │   └── routines.tal
│   ├── signed
│   │   └── routines.tal
│   ├── string
│   │   ├── macros.tal
│   │   └── routines.tal
│   └── system
│       └── routines.tal
├── rom
├── src
│   ├── assembler
│   │   ├── buffers.tal
│   │   ├── data.tal
│   │   ├── generics.tal
│   │   ├── helpers.tal
│   │   ├── primitives.tal
│   │   └── routines.tal
│   ├── debugger
│   │   ├── macros.tal
│   │   └── routines
│   │       ├── after-eval.tal
│   │       └── before-eval.tal
│   ├── lexer
│   │   ├── data.tal
│   │   └── routines.tal
│   ├── logger
│   │   ├── constants.tal
│   │   ├── data.tal
│   │   ├── error
│   │   │   └── abort.tal
│   │   ├── info
│   │   │   ├── multiline-prompt.tal
│   │   │   ├── prompt.tal
│   │   │   ├── stacks.tal
│   │   │   └── summary.tal
│   │   ├── macros.tal
│   │   ├── routines.tal
│   │   └── warn
│   │       └── redefinition.tal
│   ├── merlin
│   │   ├── buffers.tal
│   │   ├── data.tal
│   │   ├── includes.tal
│   │   ├── macros.tal
│   │   └── main.tal
│   ├── repl
│   │   ├── buffers.tal
│   │   ├── data.tal
│   │   ├── macros.tal
│   │   ├── routines.tal
│   │   └── symbols.tal
│   └── tokenizer
│       ├── buffers.tal
│       └── routines.tal
└── test
    ├── macros.tal
    ├── opctest.tal
    ├── routines.tal
    └── script.tal

  ´\|/`  Merlin OS -- v0.e (18M06)
  (⏑⏑⏑)  (c) 2024 Ismael Venegas Castello
    ˅    Type 'bye' to exit.

Ready