Programming Statements

Modules

Modules are used for

creating groups of statements that can be invoked as a unit from anywhere in the program, that is, making a subroutine or function
creating a separate (symbol-table) environment, that is, defining variables that are local to the module rather than global

A module always begins with the START statement and ends with the FINISH statement. Modules can be thought of as being either functions or subroutines. When a module returns a single parameter, it is called a function and is executed as if it were a built-in IML function; a function is invoked by its name in an assignment statement rather than in a CALL or RUN statement. Otherwise, a module is called a subroutine, and you execute the module in either the RUN statement or the CALL statement.

Defining and Executing a Module

Nesting Modules

Understanding Symbol Tables

Modules with No Arguments

Modules with Arguments

More about Argument Passing

Module Storage

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