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I have trouble understanding this kind of talk. What's a problem domain, what's its dimension and normalization, and what's the high order logic all about? Can

• bob1029 6y ago
  Problem domain = Shopping, Banking, Coffee Shop, Factory, Airplane Dimension = Customers, Accounts, Users, Widgets, Inventory Higher-Order Logic = combining basic functional building blocks in order to compose more complex functionality. SQL enables direct, declarative access to the whole space of higher-order functions. E.g. You want the list of widgets made 3 quarters ago but scoped to one factory line, and only when a certain rotation of employees was on the factory floor? You got it. That's like 10-15 lines of SQL.
  • chj 6y ago
    Thanks. That is clear.
    • carapace 6y ago
      BTW all those terms are like a century old.
      • chj 6y ago
        I only saw them occasionally, never tried to understand them before.
  • garethrowlands 6y ago
    A higher order function is a function that takes another function as a parameter or returns a function as its result. Famous higher order functions include "map" and "filter", for example. Javascript, for example, uses higher order functions all the time. See [1]. The term "higher order logic" typically means program logic that uses higher order functions. An object-oriented programming style is inherently higher order because objects typically contain functions and are passed to methods. The term "higher order logic" can also mean a system of logic that allows statements about logical statements. [2] [1] https://en.wikipedia.org/wiki/Higher-order_function https://en.wikipedia.org/wiki/Higher-order_function [2] https://en.wikipedia.org/wiki/Higher-order_logic https://en.wikipedia.org/wiki/Higher-order_logic