•prefs — Display settings

•prefs Y applies the settings in the record Y to this session’s display, and returns every setting. •prefs ⍬ changes nothing.

Setting	Holds	Default
box	$t draws arrays in boxes	$t in the REPL and the BPL Jupyter kernel, $f elsewhere
trees	$t shows functions and dissected expressions as trees; $f uses linear notation. Independent of box	as box
fns	$f leaves output made inside functions unboxed	as box
dissect	$t shows the bound expression before each normal result, using trees	$f
limit	The most items display shows in full. ∞ shows every item	1000
edges	Positions shown at each end of a long axis	3
prec	Significant digits shown for each float. ∞ shows every digit	10
width	The widest line display shows. ∞ allows any width	The terminal’s width in the REPL, ∞ elsewhere

Display shows part of an array of more than limit items: the first and last edges positions of each axis longer than twice edges. … replaces the hidden columns, ⋮ the hidden rows, and ⋱ sits where they cross. A nested array follows the same rule on its own. A line wider than width hides columns in the same way, keeping as many at each end as fit. ⎕← always shows every item, and rounds floats to prec as display does. ⍕ and source text always hold every item and every digit.

Errors: DOMAIN for an unknown setting or an invalid value.