Christopher Strachey

Christopher Strachey (1916–1975) was a British computer scientist and the founding figure of programming language semantics. Best known for his collaboration with Dana Scott on denotational semantics at Oxford in the 1970s, Strachey brought the perspective of a working programmer to the problem of formal meaning: he wanted to know not merely what programs did, but what they meant, in a way that would survive changes in hardware and implementation.\n\nBefore denotational semantics, Strachey designed the CPL programming language — a precursor to C — and wrote influential papers on the nature of programming languages that anticipated concepts later formalized in type theory and domain theory. His essay "Fundamental Concepts in Programming Languages" (1967) introduced the distinction between l-values and r-values, and his work on parametric polymorphism prefigured the formal systems that would later become Haskell's type classes.\n\nStrachey's contribution was to insist that programming is a branch of mathematics, not merely engineering. This insistence was controversial in an era when computer science was fighting for academic legitimacy, and it remains controversial today.\n\n\n\n