Function boxedToUnitExpression

src/compute-engine/library/units.ts:23–57

(expr: Expression)

 * `UnitExpression` (string or JSON array) that `unit-data.ts` functions
 * can work with.
 */
export function boxedToUnitExpression(expr: Expression): UnitExpression | null {
  if (!expr) return null;

  // Simple symbol unit
  if (isSymbol(expr)) return expr.symbol;

  if (!isFunction(expr)) return null;

  const op = expr.operator;
  if (op === 'Multiply') {
    const parts: UnitExpression[] = [];
    for (const child of expr.ops) {
      const c = boxedToUnitExpression(child);
      if (!c) return null;
      parts.push(c);
    }
    return ['Multiply', ...parts];
  }

  if (op === 'Divide') {
    const a = boxedToUnitExpression(expr.op1);
    const b = boxedToUnitExpression(expr.op2);
    if (!a || !b) return null;
    return ['Divide', a, b];
  }

  if (op === 'Power') {
    const base = boxedToUnitExpression(expr.op1);
    const exp = expr.op2?.re;
    if (!base || exp === undefined) return null;
    return ['Power', base, exp];
  }

  return null;
}

export const UNITS_LIBRARY: SymbolDefinitions = {