BeanShell Dynamic Typing
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## BeanShell Dynamic Typing

Without an explicit type declaration like `String` `result`, BeanShell variables can change their type at runtime depending on the object or data assigned to it. This dynamic typing allows you to write code like this (if you really wanted to):

    // note: no type declaration
    result = Macros.input(view, “Type something here.”);

    // this is our predefined, current View
    result = view;

    // this is an “int” (for integer);
    // in Java and BeanShell, int is one of a small number
    // of “primitive” data types which are not classes
    result = 14;

However, if you first declared `result` to be type `String` and and then tried these reassignments, BeanShell would complain. While avoiding explicit type declaration makes writing macro code simpler, using them can act as a check to make sure you are not using the wrong variable type of object at a later point in your script. It also makes it easier (if you are so inclined) to take a BeanShell “prototype” and incorporate it in a Java program.

One last thing before we bury our first macro. The double slashes in the examples just above signify that everything following them on that line should be ignored by BeanShell as a comment. As in Java and C/C++, you can also embed comments in your BeanShell code by setting them off with pairs of `/* */`, as in the following example:

    /* This is a long comment that covers several lines
    and will be totally ignored by BeanShell regardless of how
    many lines it covers */

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