The DEFINE clause

The DEFINE clause can be used to define program variables with a scope that is local to the declarative dialog block.

This clause must be placed before any other sub-dialog block:

DIALOG ()
    DEFINE checked BOOLEAN,
           tmp STRING

    INPUT BY NAME ...
        ...
    END INPUT

END DIALOG

The DEFINE clause is only allowed in declarative dialog blocks. Variables used locally in a procedural dialog block should be defined in the scope of the function containing the procedural dialog block.