Px compilers

The Pascal-P compiler was created in 1973, then went through several versions, which so far have not been available. Ch. Jacobi gives an overview of the Pascal-P versions in PUG newsletter #4:

Name Origination Year Source Description
Pascal P1 Zurich 1973 No Either of the early Pascal-P systems (released in March and July 1973 respectively)
Pascal-P2 Zurich 1974 Yes The Pascal-P system released in May 74
Pascal-P3 Zurich 1976 No The new Pascal-P system with the same hypothetical machine as the one underlying the Pascal P2 system
Pascal-P4 Zurich 1976 Yes The new Pascal-P system with a slightly modified hypothetical machine (allowing a more efficient implementation)

The versions of P1 that existed have (so far) not been available. The revised version, P2, is available, and was used as the basis for the UCSD system. P3 was a “step” implementation used to bridge between P2 and P4, and is also not obtainable.

The last major version of Pascal-P was P4.