Maybe the most notable system that had "files as structured data" is the IBM S/360 lineage of mainframes. > In the context of IBM mainframe computers in the S/

Maybe the most notable system that had "files as structured data" is the IBM S/360 lineage of mainframes. > In the context of IBM mainframe computers in the S/360 line, a data set (IBM preferred) or dataset is a computer file having a record organization. > Data sets are not unstructured streams of bytes, but rather are organized in various logical record[3] and block structures determined by the DSORG (data set organization), RECFM (record format), and other parameters https://en.wikipedia.org/wiki/Data_set_(IBM_mainframe) https://en.wikipedia.org/wiki/Data_set_(IBM_mainframe) Remarkably S/360 predates UNIX by several years, so its definitely not a novel concept. Albeit apparently IBM systems cost order of magnitude more than PDPs of the time. Of course there are also classic LISP machines where afaik pretty much everything was a SEXPR, but I have even less knowledge about the details of those.