I think you're thinking of Cornell's PL/C compiler (Watfiv was for Fortran, and didn't have a lot of error-correction), circa 1970ish. PL/C would famously convert
PTU LIST('Hello, world!
into a valid program (in fact, the claim was that it would never fail to convert any string of text into a valid program).
PL/C made a lot of sense when short student programs were entered on punched cards (and hence trivial typos were tedious to correct) and batch turnaround times were measured in hours. This makes much less sense when (a) editors can give us clues about typos right away, e.g., by indenting in a surprising way, and (b) compile times for short modules are very short.
Yes, you’re right - it’s been a long time. So long, in fact that I was using punch cards at the time. I remember getting my printouts and wondering at the results only to realize that it had converted bad input text into a “valid” program. Good times.
PTU LIST('Hello, world!
into a valid program (in fact, the claim was that it would never fail to convert any string of text into a valid program).
PL/C made a lot of sense when short student programs were entered on punched cards (and hence trivial typos were tedious to correct) and batch turnaround times were measured in hours. This makes much less sense when (a) editors can give us clues about typos right away, e.g., by indenting in a surprising way, and (b) compile times for short modules are very short.