Reading through a CACM publication, I'm struck by how they call the whole system the "IPL Computer" -- they were specifying a bytecode VM. It looks like early IPLs dated to the 1950s, so they'll get a pass for the actual language...

I didn't realize IPL lasted that long since indeed it's mentioned by mccarthy as a strong influence.. somehow I always assumed it meant pre-1959.

btw, for people who were there at the time, even considering the bare metal assembly nature of IPL, were people already approaching solutions similarly to lispers in the 60s ? aka dynamic generic lists, tree traversals etc