In my first job as a Real Programmer (rather than as a tech writer looking for excuses to write code), one of my first tasks was adding features to a script tha

In my first job as a Real Programmer (rather than as a tech writer looking for excuses to write code), one of my first tasks was adding features to a script that read a particular kind of XML file. The parser, such as it was, was entirely hand-rolled; if you changed an input file so that it had a space in between tags instead of a newline, the whole thing would break. I wasted no time rewriting it to use XML::Parser. In my second job as a Real Programmer, I had to add features to a script that parsed scripts in the Informix Perform Screen language. Again, this was hand-rolled. I wasted no time rewriting it to use Parse::RecDescent. I think simply knowing where to look things up puts you in the top half of professional programmers. Possibly the top quartile.