Tony Hoare has died

“Tony Hoare, inventor of quicksort and the null reference, has died at 91.”

Hoare invented quicksort, CSP, and a half dozen other things any working programmer uses every day without thinking. He also invented the null reference, which he later called his billion-dollar mistake, the most honest self-assessment any computer scientist has ever made. The field is poorer for his absence and richer for the work he leaves behind.