I've always wondered if there's more to FP than (more or less) point-free style with an associated algebra. TFA seems to stop just when it might get interesting. Did Backus ever develop (or aim for) a notion of semantic completeness, e.g. Cartesian closure or whatever works [0] for Hughes's Arrows? The last has the interesting property of being foundationally point-free but also supporting a syntax with variables (with non-standard scoping rules). Which perhaps refutes Backus's original concerns.
Thanks very much; I in turn will add a link the Related Resources section. If you'd like to be recognized as other than metazip then let me know via email.
> [...] At that time, John was interested in pure functional programming, with no side-effects on storage or the external world. I advocated extending the language to allow writing complete interactive applications. John conceded the importance of this, and came up with a scheme in which one would write a function to express the complete transformation of an application on the global state. I struggled with John’s variable free style, and suggested we allow lambda variables when defining a new functional form (higher-order function), but he stuck to his guns.
(In my project) I’ve reduced extensibility to the meta-composition rule, and I’m using an IO monad for interaction because I believe all functions should remain as simple as possible.
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[ 4.5 ms ] story [ 23.6 ms ] thread[0] https://en.wikipedia.org/wiki/Arrow_(computer_science)
> [...] At that time, John was interested in pure functional programming, with no side-effects on storage or the external world. I advocated extending the language to allow writing complete interactive applications. John conceded the importance of this, and came up with a scheme in which one would write a function to express the complete transformation of an application on the global state. I struggled with John’s variable free style, and suggested we allow lambda variables when defining a new functional form (higher-order function), but he stuck to his guns.
(In my project) I’ve reduced extensibility to the meta-composition rule, and I’m using an IO monad for interaction because I believe all functions should remain as simple as possible.