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Christopher Strachey the designer of CPL deserves a shout out. He also wrote a very early checkers program, invented time sharing, created denotational semantic

Christopher Strachey the designer of CPL deserves a shout out. He also wrote a very early checkers program, invented time sharing, created denotational semantics with Dana Scott, came up with the idea of L values and R values, and coined the term currying.

skissane 2y ago
> Christopher Strachey the designer of CPL deserves a shout out. He also wrote a very early checkers program, invented time sharing Did he invent time sharing? He presented a very influential paper on the topic at the 1959 UNESCO International Conference on Information Processing in Paris. But, John McCarthy says he was already thinking about the topic in 1955. [0] And John Backus proposed the idea at an MIT conference in 1954. [1] So, while no doubt he played a big role in popularising the concept, it is questionable whether he actually "invented" it. Maybe, he came up with the idea independently of McCarthy and Backus – but if that is true, it isn't clear that he thought of it first [0] https://www-formal.stanford.edu/jmc/history/timesharing/timesharing.html https://www-formal.stanford.edu/jmc/history/timesharing/time... [1] https://bitsavers.org/pdf/mit/whirlwind/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdf https://bitsavers.org/pdf/mit/whirlwind/summer_session_1954/... see PDF page 78, in particular "John Backus said that by time sharing, a big computer could be used as several small ones; there would need to be a reading station for each user" (my emphasis)
- vajrabum 2y ago
  Got it. But he did get a patent for the invention.
  - skissane 2y ago
    Getting a patent doesn’t mean no prior art exists, it just means the Patent Office can’t find it. That’s true today, but was even more true in the 1950s/1960s when patent offices had access to far less information. It is easy for us to find this 1954 conference proceedings from MIT, how would a patent examiner back then find it, or even know to look for it?
    - vajrabum 2y ago
      Makes perfect sense, and important ideas tend to occur in multiple places over a shortish period of time.

skissane 2y ago

> Christopher Strachey the designer of CPL deserves a shout out. He also wrote a very early checkers program, invented time sharing Did he invent time sharing? He presented a very influential paper on the topic at the 1959 UNESCO International Conference on Information Processing in Paris. But, John McCarthy says he was already thinking about the topic in 1955. [0] And John Backus proposed the idea at an MIT conference in 1954. [1] So, while no doubt he played a big role in popularising the concept, it is questionable whether he actually "invented" it. Maybe, he came up with the idea independently of McCarthy and Backus – but if that is true, it isn't clear that he thought of it first [0] https://www-formal.stanford.edu/jmc/history/timesharing/timesharing.html https://www-formal.stanford.edu/jmc/history/timesharing/time... [1] https://bitsavers.org/pdf/mit/whirlwind/summer_session_1954/Digital_Computers_Advanced_Coding_Techniques_Summer_1954.pdf https://bitsavers.org/pdf/mit/whirlwind/summer_session_1954/... see PDF page 78, in particular "John Backus said that by time sharing, a big computer could be used as several small ones; there would need to be a reading station for each user" (my emphasis)

vajrabum 2y ago
Got it. But he did get a patent for the invention.
- skissane 2y ago
  Getting a patent doesn’t mean no prior art exists, it just means the Patent Office can’t find it. That’s true today, but was even more true in the 1950s/1960s when patent offices had access to far less information. It is easy for us to find this 1954 conference proceedings from MIT, how would a patent examiner back then find it, or even know to look for it?
  - vajrabum 2y ago
    Makes perfect sense, and important ideas tend to occur in multiple places over a shortish period of time.