(a) A is the amount by whichi. the aggregate of all amounts deducted under paragraph b.1 of section 257 in computing, immediately before the disposition, the adjusted cost base to the taxpayer of the shares disposed of, exceeds
ii. the amount that would be, but for subparagraph b of the first paragraph of section 234, the taxpayer’s capital gain for the taxation year that includes the time of the disposition, from the disposition of the shares disposed of;