The LifeLines programming language provides an include feature. Using this feature one LifeLines program can refer to other LifeLines programs. This feature is provided by the include statement:
include(string)where string is a quoted string that is the name of another LifeLines program file. When an include statement is encountered, the program that it refers to is read at that point, exactly as if the contents of included file had been in the body of the original file at that point. This allows you to create LifeLines program library files that can be used by many programs. Included files may in turn contain include statements, and so on to any depth. LifeLines will use the LLPROGRAMS shell variable, if set, to search for the include files.