FixedDecimal._alignedSum

private

FixedDecimal!(I,  - 1) _alignedSum(bool  sub)(
          FixedDecimal!(I,  - 1)  a,  FixedDecimal!(I,  - 1)  b)

static @safe pure

Adds or subtracts two runtime-form operands of this storage class, aligning to the larger scale (checked upscaling; the aligned sum must fit the precision or the operation throws).

Design record: doc/DDN-DECIMAL-ARITHMETIC.md D1/D2/D3.