export enum OpCode {
  // stack
  PUSH,  // operand: constant index (number) | stack: [] → [value]
  POP,   // operand: none | stack: [value] → []
  DUP,   // operand: none | stack: [value] → [value, value]

  // variables
  LOAD,     // operand: variable name (identifier) | stack: [] → [value]
  STORE,    // operand: variable name (identifier) | stack: [value] → []
  TRY_LOAD, // operand: variable name (identifier) | stack: [] → [value] | load a variable (if found) or a string

  // math (coerce to number, pop 2, push result)
  ADD,   // operand: none | stack: [a, b] → [a + b]
  SUB,   // operand: none | stack: [a, b] → [a - b]
  MUL,   // operand: none | stack: [a, b] → [a * b]
  DIV,   // operand: none | stack: [a, b] → [a / b]
  MOD,   // operand: none | stack: [a, b] → [a % b]

  // comparison (pop 2, push boolean)
  EQ,    // operand: none | stack: [a, b] → [a == b] (deep equality)
  NEQ,   // operand: none | stack: [a, b] → [a != b]
  LT,    // operand: none | stack: [a, b] → [a < b] (numeric)
  GT,    // operand: none | stack: [a, b] → [a > b] (numeric)
  LTE,   // operand: none | stack: [a, b] → [a <= b] (numeric)
  GTE,   // operand: none | stack: [a, b] → [a >= b] (numeric)

  // logical
  NOT,   // operand: none | stack: [a] → [!isTrue(a)]

  // control flow
  JUMP,           // operand: relative offset (number) | PC-relative jump
  JUMP_IF_FALSE,  // operand: relative offset (number) | stack: [condition] → [] | jump if falsy
  JUMP_IF_TRUE,   // operand: relative offset (number) | stack: [condition] → [] | jump if truthy
  BREAK,          // operand: none | unwind call stack to break target

  // exception handling
  PUSH_TRY,      // operand: absolute catch address (number) | register exception handler
  PUSH_FINALLY,  // operand: absolute finally address (number) | add finally to current handler
  POP_TRY,       // operand: none | remove exception handler (try completed successfully)
  THROW,         // operand: none | stack: [error] → (unwound) | throw exception

  // functions
  MAKE_FUNCTION, // operand: function def index (number) | stack: [] → [function] | captures scope
  CALL,          // operand: none | stack: [fn, ...args, posCount, namedCount] → [result] | marks break target
  TAIL_CALL,     // operand: none | stack: [fn, ...args, posCount, namedCount] → [result] | reuses frame
  RETURN,        // operand: none | stack: [value] → (restored with value) | return from function
  TRY_CALL,      /// operand: variable name (identifier) | stack: [] → [value] | call a function, load a variable, or load a string

  // arrays
  MAKE_ARRAY,  // operand: item count (number) | stack: [item1, ..., itemN] → [array]
  ARRAY_GET,   // operand: none | stack: [array, index] → [value]
  ARRAY_SET,   // operand: none | stack: [array, index, value] → [] | mutates array
  ARRAY_PUSH,  // operand: none | stack: [array, value] → [] | mutates array
  ARRAY_LEN,   // operand: none | stack: [array] → [length]

  // dicts
  MAKE_DICT,   // operand: pair count (number) | stack: [key1, val1, ..., keyN, valN] → [dict]
  DICT_GET,    // operand: none | stack: [dict, key] → [value] | returns null if missing
  DICT_SET,    // operand: none | stack: [dict, key, value] → [] | mutates dict
  DICT_HAS,    // operand: none | stack: [dict, key] → [boolean]

  // strings
  STR_CONCAT,  // operand: value count (number) | stack: [val1, ..., valN] → [string] | concatenate N values

  // typescript interop
  CALL_NATIVE, // operand: function name (identifier) | stack: [...args] → [result] | consumes entire stack

  // special
  HALT         // operand: none | stop execution
}