官术网_书友最值得收藏!

Preface

Functional programming is a style of constructing the elements and structure of a computer program by composing pure functions, avoiding shared state, mutable data, and side-effects, like we usually see in mathematics. The variable in the code function represents the value of the function parameter, and it is similar to the mathematical function. The idea is that a programmer defines the functions that contain the expression, definition, and the parameters that can be expressed by a variable to solve problems.
Functional programming is declarative rather than imperative, which means programming is done with expressions or declarations instead of statements. The application state of functional programming flows through pure functions, so it avoids the side effect. In contrast to imperative programming, the application state is usually shared and collocated with methods in objects. In imperative programming, the expressions are evaluated, and the resulting value is assigned to variables. For instance, when we group a series of expressions into a function, the resulting value depends upon the state of variables at that point in time. Because of the continuous changes in state, the order of evaluation matters. In functional programming, destructive assignment is forbidden, and each time an assignment happens, a new variable is induced. Best of all, functional code tends to be more concise and predictable, and easier to test than imperative or object-oriented code.
Although there are some specifically designed languages for functional programming, such as Haskell and Scala, we can also use C++ to accomplish designing functional programming, as we will discuss throughout this book.

主站蜘蛛池模板: 定边县| 沁水县| 辽阳市| 通海县| 镇康县| 罗甸县| 无锡市| 嘉定区| 西乌珠穆沁旗| 松潘县| 玉林市| 吉安市| 阿克苏市| 炉霍县| 马鞍山市| 吴江市| 班玛县| 泰兴市| 渝中区| 长子县| 阳信县| 宜州市| 新安县| 岑巩县| 岢岚县| 佳木斯市| 布拖县| 梁河县| 托克托县| 邵武市| 拉孜县| 建阳市| 平原县| 东安县| 资兴市| 韶山市| 长治市| 黔南| 宁海县| 怀宁县| 南汇区|