Lambda calculus is a model of computation devised in the 1930s by Alanzo Church. It’s one process for formalizing a method. Like Turing machines it formalizes the concept of effective computability, thus determining which problems or classes of problems, can be solved. You might be thinking but thats Calculus(Math), how is it related to functional programming or programming in general. It is indeed deeply related.
Lambda expressions in functional programming…
The central concept in the lambda calculus is an expression generated by the following grammar which can denote a function definition, function application.variable, or parenthesized expression. We can think of a lambda-calculus expression as a program which when evaluated by beta-reductions returns a result consisting of another lambda-calculus expression.
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