5.25. Perl next statement

发布时间 :2023-10-20 23:00:04 UTC      

Perl next statement is used to stop execution from the next the statement between the beginning of the next statement of the statement and the identifier at the end of the loop is transferred to execution continue statement block, and then return to the beginning of the loop body to start the next loop.

5.25.1. Grammar #

The syntax format is as follows:

next [ LABEL ];

Among them, LABEL is optional. If LABEL is not specified, the next statement will return to the beginning of the loop body to start executing the next loop.

Example #

#!/usr/bin/perl$a=10;while($a<20){if($a==15){#
Jump out of iteration $a=$a+1;next;}print"The value of a is :$a\\n";$a=$a+1;}

Execute the above program, and the output is as follows:

The value of a is: 10
The value of a is: 11
The value of a is: 12
The value of a is: 13
The value of a is: 14
The value of a is: 16
The value of a is: 17
The value of a is: 18
The value of a is: 19

Principles, Technologies, and Methods of Geographic Information Systems  102

In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress.