When the macro processor executes a macro program statement that can create a macro variable (such as a %LET statement), the macro processor attempts to change the value of an existing macro variable ...

A variable's name is known as an identifier. The identifier given to a variable usually follows certain rules: It can contain letters and numbers but must start with a letter. It must contain at least ...

There are some issues to consider when using local variables instead of global variables. How can the value of a variable in one sub-program be accessible to another sub-program? What happens if the ...