\d .show

/ L[`v`r`tr`bl`b`t`l`h`i`br`tl]:_ci,/179 191 217+!:'2 7 2;LL[`v`b`t`i]:_ci 186 208 210 215  // windows
L[`v`r`tr`bl`b`t`l`h`i`br`tl]:"|++++++-+++";LL[`v`b`t`i]:"|+++"
P:20                                                            / print width
box:{:[emp x;,," ";5=t:4:x;dic x;~t;mat x;fmt x]}               / box logic
fmt:{,wid[@x]_ssr[5:x;"\n";";"]}                                / format value
wid:{:[x|P>#y;y;(P#y),".."]}                                    / format width
sep:{,'/|@[|L.v,''x;0;{x,'L.v}]}                                / vertical separation
edg:{(,1!L[x],1_-1_ L[`h,y][L.v=*z]),z}                         / edges
top:edg[`tr`tl;`t]                                              / top edge
mid:edg[`r`l;`i]                                                / middle edge
bot:|edg[`br`bl;`b]@|:                                          / bottom edge
two:{:[(#*x)=i:(+\L.t=*x)?2;x;.[x;(;i);LL[]L[!LL]?]]}           / values + attributes
enc:two top 1_ bot@,/(mid sep@)'                                / enclose
pad:{{y,((x-#y),#*y)#""}[|/#:'x]'x}                             / pad with blanks
emp:_in[;(;.();())]                                             / empty or nil?
nul:{:[&/emp'x[;2];2#'x;x]}                                     / null handler
hor:pad@box'                                                    / horizontals
ver:+:'pad@+:'                                                  / verticals
unt:{+(+y)_di x}                                                / untick
dic:unt[1]enc@+ver'+hor'nul@.:                                  / dict
mat:{unt[1+!3]cmp[x]box@.+(`$"f",/:$!#x;x)}                     / matrix
cmp:{:[~2=#^x;y;y _di -1_1_&y[;0]_lin L`tl`bl`l]}               / compress
show:`0:1!"\n",,/"\n",'box@                                     / entry point

\

d.a:.+(`x`y;10 20)
d.a..k:"a string"
d.a..l:`a_symbol
d.b.c:20 30
d.b.d:40 50 60
d.e.f.g:(2 3#!6;.[.+(`q`r;(1 2 3;`a`b`c));`r.;:;.+(`m`n`o;80 90 100)])

show d

\

+-+------------------------------+--------------+
|a|+-+--+                        |+-+----------+|
| ||x|10|                        ||k|"a string"||
| |+-+--+                        |+-+----------+|
| ||y|20|                        ||l|`a_symbol ||
| |+-+--+                        |+-+----------+|
+-+------------------------------+--------------+
|b|+-+--------+                  |              |
| ||c|20 30   |                  |              |
| |+-+--------+                  |              |
| ||d|40 50 60|                  |              |
| |+-+--------+                  |              |
+-+------------------------------+--------------+
|e|+-+--------------------------+|              |
| ||f|+-+----------------------+||              |
| || ||g|+--------------------+|||              |
| || || ||+-----+             ||||              |
| || || |||0 1 2|             ||||              |
| || || |||3 4 5|             ||||              |
| || || ||+-----+             ||||              |
| || || ||+-+--------+-------+||||              |
| || || |||q|1 2 3   |       |||||              |
| || || ||+-+--------+-------+||||              |
| || || |||r|`a `b `c|+-+---+|||||              |
| || || ||| |        ||m|80 ||||||              |
| || || ||| |        |+-+---+|||||              |
| || || ||| |        ||n|90 ||||||              |
| || || ||| |        |+-+---+|||||              |
| || || ||| |        ||o|100||||||              |
| || || ||| |        |+-+---+|||||              |
| || || ||+-+--------+-------+||||              |
| || || |+--------------------+|||              |
| || |+-+----------------------+||              |
| |+-+--------------------------+|              |
+-+------------------------------+--------------+

or:

http://www.nsl.com/k/box.png