perl check if hash value exists

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

Syntax There are only two ways to create a 'quot. Create reference Create Rule 1If you add a '/' sign before a variable, you will get the 'quota' of the variable '. $ Aref = // @ array; # $ Aref saves the 'quot' pointing to @ Array'$ Href =/% hash;

Perl Learning 5 Hash, perllearninghash [This article is original. Do not reprint it without permission] Hash is a data structure. It is similar to an array in that it can accommodate any number of values and can be used as needed. The difference

What is Perl? Perl is a free and open-source scripting language created by Larry Wall. This language is mainly intended for practical and rapid development, Structured Programming is incompatible with the popular object-oriented programming.

transferred from: http://perl.apache.org/docs/general/perl_reference/perl_reference.html Use (), require (), do (),%inc and @INC explained The @INC array @INC is a special Perl variable which is the equivalent of the shell ' s PATH variable.

From: http://perl.apache.org/docs/general/perl_reference/perl_reference.html Use (), require (), Do (), % INC and @ INC explained   The @ INC Array @ INCIs a special Perl variable which is the equivalent of the shell'sPathVariable.

The first time I came into contact with Perl was in February October 2008. At that time, due to project reconstruction, I needed a lot of text operations, so I picked up the Perl language "text operations as my mission. Of course, the famous llama

A Perl application database uses the DBM package configured by itself to create and operate a database, therefore, the DBM package and other similar packages can be considered as a database extension. The other is to use the DBI package or similar

Chapter 2: List and array list (): Empty list, false when used as a condition judgment Two non-empty list examples: ("hello", "world", "\ n") (123,456,789) Different types of elements can be contained in the same list. The list in Perl is only

1. perl ~~ For intelligent matching, it can intelligently Determine operations based on the operands on both sides of the symbol. To determine whether an element exists in an array, do not use smart matching. The program is like this: my $x=2;my