1. First-class对象的定义 2. 函数基本定义 3. 将函数当作对象 4. 高阶函数(Higher-Order Functions) 5. 匿名函数(Anonymous Functions) 6. 可调用对象(Callable Objects) 7. 位置(Positional)参数、关键词(Keyword-only)参数 8. 函数式编程 参考:Ramalho, L. (2015). Fluent python: Clear, concise, and...
2. Higher-Order Functions# A function that takes a function as argument or returns a function 1 2 3 4 5 fruits = ['fig', 'apple', 'cherry'] print sorted(fruits, key=len) # ['fig', 'apple', 'cherry'] # Any one-argument function can be used as the key. print sorted(fruits...
A function can be stored in a value or variable, passed to a function, returned from a function, and used with data structures to support map(), reduce(), fold(), and filter(), among many other higher-order functions. In this chapter, we will explore Scala’s use of first-class ...
1.1Higher-order functions: passing functions as arguments 1.2Anonymous and nested functions 1.3Non-local variables and closures 1.4Higher-order functions: returning functions as results 1.5Assigning functions to variables 1.6Equality of functions 2Type theory 3Language support 4See also 5Notes 6References...
Scala里的函数是一个“头等函数”(first-class value)。像其他的值,函数可以被当成参数传递,也可以被当成结果返回。这种情况下的函数被称为“高阶函数”(higher-order functions) https://blog.csdn.net/snlscript/article/details/18268743 从0.16版本开始,Snail Language语言将函数作为First-Class Value。First-Clas...
Finally, our approach uses normalisation and tags parts of the query to disambiguate branches of unions. Loop-lifting has been implemented in Links by Ulrich [25], and Grust and Ulrich =-=[15]-=- recently presented techniques for supporting higher-order functions as query results. By using ...
Anonymous and nested functions[edit] Further information: Anonymous function and Nested function In languages supporting anonymous functions, we can pass such a function as an argument to a higher-order function: main = map (\x -> 3 * x + 1) [1, 2, 3, 4, 5] ...
Functions Can Be Passed to Other Functions Because functions are objects, you can pass them as arguments to other functions. Here’s a greet function that formats a greeting string using the function object passed to it and then prints it: ...
That gives us map, filter and reduce. Without higher-order functions, we couldn't have them. I don't know what else to say. It's functionality that is repeated, it's boilerplate, we get to get rid of it.Another thing is something like, what are called combinators. Combinators, ...
Use functions as arguments to other functions Use functions as return values of other functions Write a program to create an ordered collectionAof functions of a real number. At least one function should be built-in and at least one should be user-defined; try using the sine, cosine, and ...