Inspector

The value inspector allows you to inspect and navigate the structure of data. While you can use it for pretty much anything (e.g. primitive data types, var, ref types) it’s most useful when you’re dealing with (deeply) nested collection-like data types (e.g. a vector of maps).

Usage

Typing C-c M-i (cider-inspect) after some form in a source buffer or the REPL will show you the structure of the form’s result in a new buffer. You can also use C-u C-c M-i to inspect the result of the current top-level form and C-u C-u C-c M-i to read an expression from the minibuffer and inspect its result.

Alternatively, after a regular eval command, you can inspect the last evaluated value using cider-inspect-last-result. When an inspector buffer is visible in the background, it is automatically updated with the last result. This behavior can be controlled with the variable cider-auto-inspect-after-eval.

The inspector can also be invoked in the middle of a debugging session, see here for more details.

You’ll have access to additional keybindings in the inspector buffer (which is internally using cider-inspector-mode):

Keyboard shortcut Description

Tab and Shift-Tab / kdb:[n] and p

Navigate inspectable sub-objects

f and b

Navigate across characters on a line

Return

Inspect sub-objects

l

Pop to the parent object

g

Refresh the inspector (e.g. if viewing an atom/ref/agent)

SPC

Jump to next page in paginated view

M-SPC

Jump to previous page in paginated view

s

Set a new page size in paginated view

c

Set a new maximum size above which nested collections are truncated

a

Set a new maximum length above which nested atoms (non-collections) are truncated

d

Defines a var in the REPL namespace with current inspector value

Configuration

By default, navigation skips over values like nils, numbers and keywords, which are not interesting to inspect. You can control this behavior using the variable cider-inspector-skip-uninteresting.

The inspector buffer is automatically selected by default. You can disable the auto selection with the variable cider-inspector-auto-select-buffer.

You can set the amount of data shown by default with the variables cider-inspector-page-size, cider-inspector-max-coll-size, and cider-inspector-max-atom-length. The values can be adjusted for the current inspector buffer using the s, c, and a keybindings.

If you enable cider-inspector-fill-frame, the inspector window fills its frame.