perl initialize array

I. Data Types(Data type): Perl has four data types: Scalar (variable), Scalar Array (Array), Hash Array (Hash), and References (pointer ), it seems to be rare, but it is more than enough to use it. Especially when writing Perl programs, you do not

1. Length of the array: If you assign an array variable to a scalar variable, the length of the array is assigned to the scalar variable: $ A = @ array; # The length of the array @ array is stored in the scalar variable $ A, that is, the number of

I. Introduction of the ModuleModule is the Perl package. The Perl object is based on a reference to the data item in the package.When you use object-oriented programming in other languages, you declare a class and then create an object (instance) of

Chapter 2: References References are declared as scalar types (named variables starting with $), and reference is obtained using the \ operator. Modifying the referenced variable is equivalent to modifying the reference pointing to the

1. Perl array (1 ): 1) initialize the array @ array = ("stringA", "stringB", "stringC ");2) print $ array [-1]; # output the stringC with the index (-1 + 3) % 3 = 23) dynamic growth $ array [4] = "stringD"; # Although $ array [3] is not used yet, it

1. Perl array (1): 1) initialize the array @ array = ("stringa", "stringb", "stringc "); 2) Print $ array [-1]; # output the stringc with the index (-1 + 3) % 3 = 2 3) dynamic growth $ array [4] = "stringd"; # Although $ array [3] is not used

1.Perl Array (1): 1 Initialize the array @array = ("Stringa", "StringB", "STRINGC");(2) using negative index loop to retrieve print $array [-1]; #输出索引为 (-1 + 3)% 3 = 2 STRINGC3 Dynamic growth $array [4] = "STRINGD"; #虽然 $array [3] has not yet been

There are five variables in Perl: Scalar, pointer, array, hash and handle. 1. scalar Let's take a look at scalar. scalar is the simplest data type in Perl. Variables of this data type can be numbers, strings, floating-point numbers, and are not

Variable scope(a) package variables$x = 1Here, $x is a package variable. There are 2 important things to know about package variables:1) If there is no other declaration, the variable is the package variable;2) package variables are always

Perl object-oriented first let's take a look at the three basic definitions of Perl Object-Oriented Programming: 1. an "object" refers to a simple reference that "there is a way to know which class it belongs. (An object is a reference variable) 2.