Local Variables

Local variables are private for each PSL process and are initialized at the start of the process. The types of local variables are:

• Named - A name is assigned to the variable by the programmer.
• Unnamed - A name is not provided, and the PATROL agent assigns one.

Named Variables

In a named variable, the PATROL agent creates a variable author and assigns it the value John Doe. The agent then executes the function nthargf(author,1) and assigns the result to a second variable named firstname. The result is that two named local variables are created. Below is an example: 

author="John Doe"; firstname=nthargf(author,1);

Unnamed Variables

In an unnamed variable, the PATROL agent automatically assigns a name because the programmer does not provide a name. Below is an example: 

firstline =nthline(cat(my le),1); 

In this example, because a name was not provided for the subfunction cat(error file), PATROL assigns it a name. The former example expands to the following: 

unnamed var=cat(myfile); firstline =nthline(unnamed var,1); 

This means that the output of every command is stored inside a variable (named or unnamed).