ЧТО БОГ НА ДУШУ ПОЛОЖИТ collsubord clauseusu. used as objfixed WO
anything one desires (may express the speaker's opinion that the thing or phenomenon in question is somehow inappropriate, of poor quality etc): whatever strikes one's fancy
whatever one feels like(to say etc) whatever comes (pops) into one's headwhatever (anything that) comes to mind.
Как-то я... решил посмотреть документацию уволенного математика. И глаза у меня буквально полезли на лоб. Он, оказывается, открыл тривиальную истину, что расчеты в этом звене вообще излишни и не влияют на последующие операции. И писал что бог на душу положит (Зиновьев 1). "Once...I decided to glance through the work of the mathematician who'd been fired. My eyes almost literally popped out. It turned out that he'd discovered the banal truth that calculations at this stage of the operation were totally unnecessary and had no influence on the subsequent stages. He just used to write whatever came into his head" (1a).

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