是什么 ->箭头在 Perl 中做什么? [英] What does the -> arrow do in Perl?

问题描述

我一直在代码中看到 -> ，但我不确定它的含义.例如:

I keep seeing -> in code and I am not exactly sure what it means. For example:

@top_links = @{$m->links};

这条线有什么作用?另外，我可以在哪里阅读有关它的信息?

What does this line do? Also, where can I maybe read about it?

推荐答案

参见 perlop 中的箭头运算符:

"->"是一个中缀解引用运算符，就像在 C 和 C++ 中一样.如果右侧是 [...]、{...} 或 (...) 下标，则左侧必须分别是对数组、散列或子程序的硬引用或符号引用.(或者从技术上讲，一个能够保存硬引用的位置，如果它是用于赋值的数组或散列引用.)参见 perlreftut 和 perlref.

"->" is an infix dereference operator, just as it is in C and C++. If the right side is either a [...], {...}, or a (...) subscript, then the left side must be either a hard or symbolic reference to an array, a hash, or a subroutine respectively. (Or technically speaking, a location capable of holding a hard reference, if it's an array or hash reference being used for assignment.) See perlreftut and perlref.

否则，右侧是方法名或包含方法名或子例程引用的简单标量变量，左侧必须是对象(受祝福的引用)或类名(即包裹名字).请参阅 perlobj.

Otherwise, the right side is a method name or a simple scalar variable containing either the method name or a subroutine reference, and the left side must be either an object (a blessed reference) or a class name (that is, a package name). See perlobj.

这篇关于是什么 ->箭头在 Perl 中做什么?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！