Functional Programing Pt. 1

it has simpler semantics, simpler model of computation than an imperative language

functional programming language

functional programming language avoids what

changing state and mutable data

major drawback of functional programming language

inefficient execution

description of a specific computation

program

refers to the steps to compute the result

the how of the computation

acts as a black box transforming input into output

the what of the computation

it is equivalent to a mathematical function

program

A program is a function that maps inputs (X) to outputs (Y)

program as functions

Describes how to compute a value using formal parameters.

function definition

Calls a function using actual parameters.

function application

in this type of programming, variables are bound to values and cannot change.

functional programming

in this type of programming, variables refer to memory locations that store values and can change.

imperative programming

in functional programming, once a variable has a value, it cannot be changed (true or false)

true

applies function to itself as in recursive

self-application

Functions that take functions as arguments or return functions as results

higher-order function

a function that takes two functions as parameters and produces another function as its returned value.

higher-order function

a function that takes two functions as parameters and produces another function as its returned value.

composition

functions can produce results even in the presence of incomplete or malformed input

nonstrict

If a condition determines the outcome early, later expressions are not evaluated.

short-circuit evaluation

parameters are evaluated only when they are actually used in the procedure

pass by name evaluation

expressions are only evaluated when needed.

lazy evaluation

obey lazy evaluation rules, partially computed list whose remaining elements can continue to be computed up to any desired number

streams

viewed functions as "black boxes" that take inputs, process them (purely mathematical functions), and produce outputs without revealing their internal workings.

lambda calculus

who invented lambda calculus

alonzo church