LMCode Grammar, dsl.schema: 2 & DSLB v6 Bytecode

Synthesized from lmcode/spec/language.md, grammar.ebnf, schema.md, and bytecode.md. Where prose and dsl.ts / dslvm.hpp ever differ, the compiler and C++ reference verifier are authoritative.

1. EBNF Grammar Summary

chunk          = { fn_decl | rule_decl | stmt } ;
fn_decl        = "fn" IDENT "(" [ param_list ] ")" "->" TYPE block ;
rule_decl      = "@" IDENT "fn" IDENT "(" [ param_list ] ")" "->" TYPE "implements" IDENT block ;
param_list     = param { "," param } ;
param          = IDENT ":" TYPE ;

block          = "{" { stmt } "}" ;
stmt           = let_stmt | assign_stmt | return_write | if_stmt | switch_stmt
               | for_range_stmt | for_each_stmt | while_stmt
               | "break" ";" | "continue" ";" | "return" [ expr ] ";" | expr ";" ;

let_stmt       = "let" IDENT "=" expr ";" ;
assign_stmt    = IDENT "=" expr ";" ;
return_write   = "$return" [ "." IDENT | "[" expr "]" ] "=" ( expr | "null" ) ";" ;
if_stmt        = "if" "(" expr ")" block [ "else" ( if_stmt | block ) ] ;
switch_stmt    = "switch" "(" expr ")" "{" { switch_case } [ "default" ":" block ] "}" ;
switch_case    = "case" case_const ":" block ;
for_range_stmt = "for" "(" IDENT "in" "range" "(" expr "," expr ")" ")" block ;
for_each_stmt  = "for" "(" IDENT "in" expr ")" block ;
while_stmt     = "while" "(" expr ")" block ;

2. Operator Precedence & Type Rules

3. Host Schema Format (dsl.schema: 2)

Every host supplies a JSON document with "dsl.schema": 2 and a valid identifier "name". Before typechecking, parseDslSchema retains the exact raw bytes as schema.bytes (for the SHA-256 header hash) and merges the bundled lmcode_std_v3 catalog into the effective schema.

{
  "dsl.schema": 2,
  "name": "sample_shop_v1",
  "types": {
    "Money": {
      "operators": { "+": "plus", "-": "minus", "*": "times", "r*": "times", "neg": "neg" },
      "methods": {
        "cents": [{ "params": [], "returns": "int" }],
        "plus":  [{ "params": ["Money"], "returns": "Money" }],
        "minus": [{ "params": ["Money"], "returns": "Money" }],
        "times": [{ "params": ["int"], "returns": "Money" }],
        "neg":   [{ "params": [], "returns": "Money" }]
      }
    },
    "Shop": {
      "methods": {
        "add":   [{ "params": ["string", "Money"], "returns": "self" }],
        "total": [{ "params": [], "returns": "Money" }]
      }
    },
    "Ledger": {
      "methods": {
        "record": [{ "params": ["Money"], "returns": "void" }]
      }
    }
  },
  "functions": {
    "money": [{ "params": ["int"], "returns": "Money" }, { "params": ["float"], "returns": "Money" }]
  },
  "context": { "shop": "Shop", "ledger": "Ledger" },
  "enums": { "Currency": ["USD", "EUR", "JPY"] },
  "conversions": [{ "from": "int", "to": "Money", "via": "money" }],
  "interfaces": {
    "Adjuster": { "params": [{ "name": "m", "type": "Money" }, { "name": "qty", "type": "int" }], "returns": "Money" },
    "Score":    { "params": [{ "name": "m", "type": "Money" }], "returns": "int" }
  },
  "result": { "type": "Json", "nullable": true }
}

4. DSLB v6 Binary File Layout

All multi-byte integers are big-endian with zero padding. The file must end immediately after the last entry (trailing bytes or truncated reads are rejected at load time).

5. Complete DSLB v6 Instruction Set (0x01..0x36)

6. Built-In MATH Opcode IDs (0x32)

0: sin(f), 1: cos(f), 2: sqrt(f), 3: abs(f), 4: floor(f), 5: pow(f,f), 6: min(f,f), 7: max(f,f), 8: clamp(f,f,f), 9: lerp(f,f,f), 10: ease(f), 11: ease_in(f), 12: ease_out(f), 13: int(f)->i, 14: abs(i), 15: min(i,i), 16: max(i,i), 17: clamp(i,i,i).

7. Loader Error Codes