Function partBoundSubject

src/compute-engine/assume.ts:1021–1044

* Recognize a normalized-inequality lhs of the form `±Part(x) + k` where * `Part ∈ {Real, Imaginary, Abs, Argument}` and `k` is an optional numeric * constant. Returns the (non-self) subject, or `undefined`. * * Deliberately stricter than `boundsFromNormalizedInequality`: an lhs with * a non-nu

(lhs: Expression)

    if (isFunction(excluded, 'Set')) {
      // Finite exclusion set: store a disequality per element
      for (const e of excluded.ops) {
        if (storeNotEqual(ce, ce.symbol(symbol), e) === 'contradiction')
          return 'contradiction';
      }
      return 'ok';
    }
    // Non-finite exclusion: store a NotElement fact
    const r = storeNotElement(ce, ce.symbol(symbol), excluded);
    return r === 'tautology' ? 'ok' : r;
  }

  // 5. Union of intervals/ranges: refine the type only; the membership
  //    fact is stored verbatim (a union yields a disjunction of bounds,
  //    which the fact layer does not represent)
  if (isFunction(setExpr, 'Union') && setExpr.ops.length > 0) {
    if (setExpr.ops.every((s) => isFunction(s, 'Range'))) {
      if (refineSymbolType(ce, symbol, 'integer', cause) === 'contradiction')
        return 'contradiction';
    } else if (
      setExpr.ops.every(
        (s) => isFunction(s, 'Interval') || isFunction(s, 'Range')
      )
    ) {
      if (refineSymbolType(ce, symbol, 'real', cause) === 'contradiction')
        return 'contradiction';
    }