The Inspector

CCL has an inspector, an interactive tool to let you look at, and in some cases modify, Lisp objects. To inspect a Lisp object, call the function INSPECT on the object. This displays the object, showing its contents as a sequence of numbered "items". If there are a lot of items (e.g. a large array) , they're displayed in "pages", i.e. groups that you can scroll up and down through. (Each "page" is 20 lines.)

It enters a read-eval-print loop that understands the following top-level commands:

(:i N)

Inspect the N'th item, entering the inspector recursively.

:pop

Exit the current inspector level.

:show

Show (display) the object being inspected, again.

:next

Show next "page" of the object

:prev

Show previous "page" of the object

:home

Show first "page" of the object

(:s N V)

Set the value of the N'th item to V, where that can be done.

If you type in an ordinary Lisp form, it is evaluated and printed. The variable ccl::@ is bound to the object being inspected.

In the :i and :s commands, N is not evaluated, and in the :s command, V is not evaluated. (You can use the #. reader macro if you do want to get something evaluated in those positions.)