NB. 5!:5 ----------------------------------------------------------------

ar=: 5!:1

test1=: 1 : 0
 0!:10 'asdf=.',5!:5 <'x'
 assert. (ar <'x') -: ar <'asdf'
 1
)

test2=: 3 : 0
 0!:10 'asdf=.',5!:5 y
 assert. (ar y) -: ar <'asdf'
)


NB. 5!:5 nouns ----------------------------------------------------------

test=: [ -: ".@(3 : '5!:5<''y''')

test ''
test 0 1$''
test 1 0$''
test 0 3 4$'abc'
test 4 3 2 4 9 0 3 4$'Cogito, ergo sum.'
test 'j'
test ,'j'
test 5$'j'
test 13$'j'
test ''''
test ,''''
test 5$''''
test 6$''''
test 23$''''
test 24$''''
test 'sui generis'
test 'Don''t tread on me!'
test 1 1$'j'
test 1 3$'row'
test 6 1$'column'
test 2 3$'j'
test 1 13$'j'
test 13 1$'j'
test 6 12$'j'
test 2 3$''''
test 1 13$''''
test 13 1$''''
test 6 13$''''
test 3 7$'Opposable thumbs'
test 6 13$'Don''t tread on me!'
test 2 3 4$'j'
test 2 3 4$''''
test 2 3 4$'Don''t tread on me!'
test (?2 3 4 5$#a.){a.
test 'abc', a.
test 'abc',~a.
test (0    {a.), a.
test (0    {a.),~a.
test (0   1{a.), a.
test (0   1{a.),~a.
test (0   4{a.), a.
test (0   4{a.),~a.
test (_1   {a.), a.
test (_1   {a.),~a.
test (_2 _1{a.), a.
test (_2 _1{a.),~a.
test (_4 _1{a.), a.
test (_4 _1{a.),~a.
test '_' (a.i.' ')}a.
test (a.{~(i.26)+a.i.'a') ((i.26)+a.i.'A')}a.
test |.a.
test a.{~?#a.

test 0
test i.0
test i.1 0
test i.0 1
test i.0 3 4 0
test 3j4
test ,_123
test _123 2 3 4
test 0 _1.2e_3j_4.5e_6 7 8 9 0 _8
test 5$183164
test 13$183164
test x=:?13$183164
test x=:?2 3$183164
test x=:?1 1$183164
test x=:?1 7$183164
test x=:?7 1$183164
test x=:o.i.3 4
test x=:o.>:i.-4 5
test x=:r.?2 3 4$10
test j.i.4 5
test r.i.8
test i.3 4
test 5+i.3 4
test 5+2*i.3 4
test 5+_1*i.3 4
test i.-3 4
test 10$_
test 4 5$__
test 4 5$_ 0 __

test 0$<''
test 0 1$<'abc'
test 1 0$<'abc'
test 0 3 4 5 0$<'abc'
test <''
test a:
test <'j'
test <,'j'
test ,<'foobar'
test ;:'Cogito, ergo sum.'
test '' ;;:'sui generis'
test 'f';;:'sui generis'
test ,&.>'f';;:'sui generis'
test 'Opposable';'thumbs'
test 'Opposable';'thumbs '
test 2 3$'foobar';?2 3$183164
test 'abcd';5$233{a.
test <0;'abcd'
test <(,0);'abcd'
test 5!:1<'test'
test 5!:2<'test'
test 5!:4<'test'
test 5!:5<'test'

'a:' -: 5!:5 <'t' [ t=:a:


NB. 5!:5 empty arrays ---------------------------------------------------

test=: 3 : '((3!:0 x) -: 3!:0 y) *. x -: y [ x=. ".5!:5 <''y'''

test 0$0
test 0$'abc'
test 0$3 4
test 0$3.4
test 0$3j4
NB. test 0$3r4
test 0$34x
test 0$3r4
test 0$3;4
test 0$s: ' a b cd'
test 0$u: ' a b cd'

test s$0             [ s=: 0 (?#s)}s=: ?10$5
test s$'abc'         [ s=: 0 (?#s)}s=: ?10$5
test s$3 4           [ s=: 0 (?#s)}s=: ?10$5
test s$3.4           [ s=: 0 (?#s)}s=: ?10$5
test s$3j4           [ s=: 0 (?#s)}s=: ?10$5
NB. test s$3r4       [ s=: 0 (?#s)}s=: ?10$5
test s$34x           [ s=: 0 (?#s)}s=: ?10$5
test s$3;4           [ s=: 0 (?#s)}s=: ?10$5
test s$s: ' a b cd'  [ s=: 0 (?#s)}s=: ?10$5
test s$u: ' a b cd'  [ s=: 0 (?#s)}s=: ?10$5


NB. 5!:5 ----------------------------------------------------------------

+                                test1
+.                               test1
+:                               test1
j.                               test1
0:                               test1
f                                test1
+/                               test1
+./                              test1
+/ .*                            test1
3&$                              test1
,&(3 4$'asdf')                   test1
3&$ @ (,&(3 4$'asdf'))           test1
3&$ @  ,&(3 4$'asdf')            test1
3 : 'foo y'                      test1
3 : (':'; 'x bar y')             test1
3 : ('foo y'; ':'; 'x bar y')    test1
3 : (97 9 98{a.)                 test1
+/ : (- * %)                     test1
1 H. 1                           test1
*:      (2 : 'u"n y') (1;2;3)    test1
(4;5;6) (2 : 'u"n y') *:         test1
(4;5;6) (2 : 'u"n y') (1;2;3)    test1

(3x     (2&+) ])                 test1
(1 2 3x (2&+) ])                 test1
(-&3x   (2&+) ])                 test1

f =:+ 
g =:- 
f3=:$
(+ %)       test1
(+&(3) 4&*) test1
(f g)       test1
(f3 g)      test1
(+(*#))     test1
(+(*#-))    test1
((+-) (*%)) test1
((+-) (*%#))test1
(+-)/       test1
((+-*)%)    test1
((+-*)#)    test1

f=:+ 
g=:- 
h=:$
(+-*              ) test1
((+&3) 4&- *      ) test1
(+ (-&4) 5&*      ) test1
(f g %            ) test1
(% f g            ) test1
(f g h            ) test1
(f g h f          ) test1
(f g h f g        ) test1
(f g h f g h      ) test1
((f g h) f g      ) test1
((f g  ) f g      ) test1
((f g h) f g h    ) test1
((f g  ) f g h    ) test1
((+-*) % #        ) test1
((+ *) % #        ) test1
(+ (-#*) %        ) test1
(+ (- *) %        ) test1
(+ - (*%#)        ) test1
(+ - (* #)        ) test1
((+=-) (*,%) ($;#)) test1
((+ -) (* %) ($ #)) test1

(+`-`*@.i.                  ) test1
(+/`(-&.+)`(%/\.)@.(i.@])   ) test1
((+%)`(-&.+)`(%/\.)@.(i.@]) ) test1
((+-*)`(-&.+)`(%/\.)@.(i.@])) test1

a=: /
test2 <'a' 
a=: /.
test2 <'a'

c=: .
test2 <'c'
c=: :
test2 <'c'
c=: ..
test2 <'c'
c=: .:
test2 <'c'
c=: &.
test2 <'c'

a=: `]  
test2 <'a'
a=: `(+/ .* ) 
test2 <'a'
a=: `(+/%#)   
test2 <'a'
a=: `(+/`%`#) 
test2 <'a'
a=: *`         
test2 <'a'
a=: +/ .*`     
test2 <'a'
a=: (+/%#)`    
test2 <'a'
a=: +/`%`#`  
test2 <'a'
a=: (+% )`$`#` 
test2 <'a'
a=: (+-*)`$`#`  
test2 <'a'
a=: +/`%`#@.   
test2 <'a'
a=: (+% )`*`#@. 
test2 <'a'
a=: (+-*)`$`#@.
test2 <'a'
a=: +/`%`#`:0  
test2 <'a'
a=: (+% )`%`#`:0
test2 <'a'
a=: (+%-)`%`#`:0 
test2 <'a'
a=:   : -      
test2 <'a'
a=: - :      
test2 <'a'
a=: (+-)@     
test2 <'a'
a=: (+-*)@   
test2 <'a'

f=:&
g=:*
a=: f g       
test2 <'a'
a=: g f       
test2 <'a'
a=: @.(+/%#)
test2 <'a'
a=: `:0 
test2 <'a'

f=:g=:h=:/
a=: f g   
test2 <'a'     
a=: f g h      
test2 <'a'     
a=: f g h f    
test2 <'a'     
a=: f g h f g   
test2 <'a'     
a=: f g h (f g)  
test2 <'a'     
a=: f g   (f g)  
test2 <'a'     
a=: f g h (f g h)
test2 <'a'     
a=: f g   (f g h)
test2 <'a'     
a=: /\.(&+)("1)
test2 <'a'     
a=: (/\.)(+&)("1 _)

c=: 2 : '%&y@(+&y -&x ])'
test2 <'c'

test2 <'test1'
test2 <'test2'


NB. 5!:5 on "real" examples ---------------------------------------------

ar     =: 5!:1
boxed  =: 32&= @ type
oarg   =: >@(1&{)
mtv    =: i.@0:
paren  =: ('('&,)@(,&')')
symb   =: $&' '@(e.&'.:')@{. , ]
quote  =: ''''
alp    =: (,65 97+/i.26){a.
dig    =: '0123456789'

slist  =: $&','@(1&=)
shape  =: mtv`slist`(,&'$'@":)@.(2&<.@#)`('i.'&,@":) @. (0&e.) @ $
vchar  =: >:@(quote&=)@, quote&,@(,&quote)@# ,
vbox   =: }. @ ; @: (','&,@paren@('<'&,)@lnoun&.>)
value  =: vchar`vbox`(":!.18@,) @. (2 32&i.@(type * *@(*/)@$))
lnoun  =: shape , value

dotco  =: 2&=@# *. e.&'.:'@{:
name   =: e.&alp@{. *. *./@(e.&(alp,dig,'_'))@}: *. e.&(alp,dig,'_.:')@{:
num    =: e.&(dig,'_')@{. *. *./@(e.&(dig,'_ .ejdr'))
qstr   =: mtv -: -.@(~:/\)@(e.&quote) -.&quote@# ]
pstr   =: -.@(0&e.)@}:@(+/\)@({&1 _1 0)@('()'&i.)
nopar  =: 1&=@# +. dotco +. name +. num +. qstr +. pstr
cp     =: paren`] @. nopar

bp     =: ]`cp@.(' '&e.)
hfork  =: }.@;@:(' '&,@bp&.>)@]
left   =: bp@>@{.
right  =: mtv`(cp@>@{:)@.(1&<@#)
ins    =: left@] , symb@>@[ , right@]
act    =: ;@:(cp&.>)@]
insert =: hfork`hfork`act`act`act`ins @. ('23456'&i.@{.@>@[)

lx     =: {. insert lr&.>@oarg
ltie   =: lr`(}.@;@:('`'&,@cp@lr&.>)@oarg) @. ((<,'0')&=@{.)
lgl    =: {. insert (ltie&.>@{. , lr  &.>@}.)@oarg
lgr    =: {. insert (lr  &.>@{. , ltie&.>@}.)@oarg
lg     =: lgr`lgl`lx @. (i.&(<,'`')@oarg)
ltil   =: lx`(oarg@>@{.@oarg) @. ((<,'0')&=@{.@>@{.@oarg)
lcase  =: (cp@lnoun@oarg)`lgl`lgl`lg`ltil`lx @. ((;:'0@.`:4~')&i.@{.)
lr     =: symb`lcase@.boxed

lrep   =: lr @ > @ ar

test2"0 ;:'ar boxed oarg mtv paren symb quote alp dig'
test2"0 ;:'slist shape vchar vbox value lnoun'
test2"0 ;:'dotco name num qstr pstr nopar cp'
test2"0 ;:'bp hfork left right ins act insert'
test2"0 ;:'lx ltie lgl lgr lg ltil lcase lr lrep'

ar      =: 5!:1
boxed   =: 32&= @ type
mt      =: 0&e.@$
oarg    =: >@(1&{)
shr     =: |.!.''
shl     =: 1&(|.!.'')
mat     =: (1 1&}.)@(_1 _1&}.)@":@<
boxc    =: 9!:6 ''
dash    =: 10{boxc

extent  =: (+./\ *. +./\.) @ (' '&~:) @: ({."1)
limb1   =: 1&|.@$ 1&~: }. (10 6 0{boxc)&,@($&(9{boxc))
limb    =: -@(i.&1)@[ |. #@[ {. limb1@]
pfx     =: (limb +/)@extent ,. ]
pad     =: [ {. ] ,. dash&=@({:"1)@] {  ' '&,:@($&dash)@(-&{: $)
take    =: pad`($&' '@[) @. (mt@])
rc      =: #@>@{."1 ; >./@:({:@$@>)
kernt   =: (0{boxc)&=@shl@[ *. ' '&~:@]
kernb   =: (6{boxc)&=@] *. ' '&~:@shl@[
kern    =: (<0 0)&{&>"2 (kernt +./"1@:+. kernb) (<_1 0)&{&>"2
gap     =: ,&.>"_1 {&((0 1$' ');1 1$' ')@kern
graft   =: (pfx&.>@{. 0} ]) @ (,&.>/) @ gap @ ({@rc take&.> ])

lab     =: ,: @ (2&|.) @ ((' ',dash,dash,' ')&,)
label   =: lab`((,.dash)&[) @. (e.&'0123456789'@{.)
center  =: ((i.&1) -@+ <.@-:@(+/))@] |. #@] {. [
root    =: label@[ center extent@>@{.@]

leaf    =: ,@<@(((,:dash,' ')&[ center $&1@#) ,. ])@mat@":

trx     =: >@{. (root ; ]) graft@:(tr@>)@oarg
trgl    =: >@{. (root ; ]) graft@:(trx@>@{. , tr @>@}.)@oarg
trgr    =: >@{. (root ; ]) graft@:(tr @>@{. , trx@>@}.)@oarg
trg     =: trgr`trgl`trx @. (i.&(<,'`')@oarg)
trtil   =: trx`(leaf@oarg@>@{.@oarg) @. ((<,'0')&=@{.@>@{.@oarg)
trcase  =: (leaf@oarg)`trgl`trgl`trg`trtil`trx @. ((;:'0@.`:4~')&i.@{.)
tr      =: leaf`trcase @. boxed

rep     =: 2 : 'x & (((# i.@#)@,@y@])})'
right   =: (5{boxc) rep (e.&(9{boxc) *. shr"1@(e.&dash))
cross   =: (4{boxc) rep (e.&(5{boxc) *. shl"1@(e.&dash))
left    =: (3{boxc) rep (e.&(9{boxc) *. shl"1@(e.&dash))
bot     =: (7{boxc) rep (e.&(6{boxc) *. shr"1@(e.&dash))
connect =: bot @ left @ cross @ right

tree    =: connect @ > @ (,.&.>/) @ (> (root ; ]) tr@>@ar)

test2"0 ;:'ar boxed mt oarg shr shl mat boxc dash'
test2"0 ;:'extent limb1 limb pfx pad take rc kernt kernb kern gap graft'
test2"0 ;:'lab label center root leaf'
test2"0 ;:'trx trgl trgr trg trtil trcase tr'
test2"0 ;:'rep right cross left bot connect tree'

en     =: #@]
em     =: (en >.@% -@[)`(en 0&>.@>:@- [) @. (0&<:@[)
kay    =: en`em @. (0&<@[)
omask  =: (em,en) $ ($&0@|@[ , $&1@kay)

base   =: 1&>.@-@[ * i.@em
iind   =: base ,. |@[ <. en - base
seg    =: ((+i.)/@[ { ])"1 _

infix  =: 1 : '(iind  x@seg ])"0 _'
outfix =: 1 : '(omask x@#   ])"0 _'
prefix =: 1 : '>:@,.@i.@# x@{. ]'
suffix =: 1 : ',.@i.@#    x@}. ]'

key    =: 1 : '=@[ x@# ]'

osub   =: >@]`(>@[ >@:{ ]) @. (*@#@])
oind   =: (+/&i./ </.&, i.)@(2&{.)@(,&1 1)@$
ob     =: 1 : 'oind x@osub"0 1 ,@(<"_2)'

bs     =: 1 : '(x prefix) : (x infix )'
bsd    =: 1 : '(x suffix) : (x outfix)'
sd     =: 1 : '(x ob    ) : (x key   )'

test2"0 ;:'en em kay omask'
test2"0 ;:'base iind seg'
test2"0 ;:'infix outfix prefix suffix'
test2"0 ;:'key osub oind ob'
test2"0 ;:'bs bsd sd'


NB. 5!:5, handling gerunds ----------------------------------------------

fx =: 5!:0
lr =: 5!:5

g =:[`((e.&' ' # i.@#)@])`]
f =: g}
(lr<'f') -: '[`((e.&'' '' # i.@#)@])`]}'
f =: (1{g) fx}
(lr<'f') -: '(e.&'' '' # i.@#)@]}'

g =: */\.`(i.@#)`(+/~)
f =: i.^:g
(lr<'f') -: 'i.^:(*/\.`(i.@#)`(+/~))'
f =: ^:g
(lr<'f') -: '^:(*/\.`(i.@#)`(+/~))'
f =: +/\^:
(lr<'f') -: '+/\^:'
f =: i.^:*
(lr<'f') -: 'i.^:*'

g =: */\.`(+/ % #)`]
f =: `g
(lr<'f') -: '`(*/\.`(+/ % #)`])'
f =: g`
(lr<'f') -: '*/\.`(+/ % #)`]`'

g =: ]`(+%)
f =: g `:0
(lr<'f') -: ']`(+ %)`:0'
f =: g`:
(lr<'f') -: ']`(+ %)`:'
f =: `:0
(lr<'f') -: '`:0'

g =: ((%&4@# , 4:) $ ]) ` %: ` $
f =: g@.*
(lr<'f') -: '((%&4@# , 4:) $ ])`%:`$@.*'
f =: g@.
(lr<'f') -: '((%&4@# , 4:) $ ])`%:`$@.'
f =: @.('abc'&i.)
(lr<'f') -: '@.(''abc''&i.)'

4!:55 ;:'a act alp ar base bot boxc boxed bp bs '
4!:55 ;:'bsd c center connect cp cross dash dig dotco em '
4!:55 ;:'en extent f f3 fx g gap graft h hfork '
4!:55 ;:'id iind infix ins insert kay kern kernb kernt key '
4!:55 ;:'lab label lcase leaf left lg lgl lgr limb limb1 '
4!:55 ;:'lnoun lr lrep ltie ltil lx mat mt mtv name '
4!:55 ;:'nopar num oarg ob oind omask osub outfix pad paren '
4!:55 ;:'pfx prefix pstr qstr quote rc rep right root '
4!:55 ;:'s sd seg shape shl shr slist suffix symb '
4!:55 ;:'t take test test1 test2 tr trcase tree trg trgl trgr trtil trx '
4!:55 ;:'value vbox vchar x '