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This article mainly talks about "the declaration and call of Perl function in Perl". Interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn the declaration and call of Perl function in Perl.

Perl function

The Perl function in Perl is basically the same as in C language, except that there are some differences in declaration and call, which are not as strict as C language.

I. declaration and call of Perl function

Declare subfunction_name {}

Call dofunction_name

& function_name does not need to be declared first.

2. Local variables in Perl function

My$a

My ($a. M. B)

Local ($a)

The difference is that the variable defined by my exists only in the subroutine, while the variable defined by local does not exist in the subroutine, but exists in the subroutine and the subroutine called by the subroutine.

3. The predefined subroutine in the Perl function

Perl5 predefines three subroutines, which are executed at a specific time. They are: begin subroutine is called when the program starts; end subroutine is called at the end of the program; AUTOLOAD subroutine is called when a subroutine can not be found. You can define them yourself to perform the desired actions at a specific time. Such as:

BEGIN {print ("Hidden WelcometoPerl!\ n");} AUTOLOAD {print ("subroutine$AUTOLOADnotfound\ n"); # variable $AUTOLOAD is the name of the unfound subroutine print ("argumentspassed:@_\ n");}

If multiple subroutines are defined in the same predefined subroutine, BEGIN executes sequentially and END executes in reverse order.

At this point, I believe you have a deeper understanding of "the declaration and call of Perl function in Perl". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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