ANN: heavy updates to inca, apl calculator in (overly-)terse C

[luser droog]

The inca interpreter has incorporated strange new features
in the area of programmability and accessibility.
It is available in an online version compiled to javascript
courtesy of Thomas Baruchel http://baruchel.hd.free.fr/apps/apl/inca/
as well as the master repo
https://github.com/luser-dr00g/inca

Essentially, the change over the previous announcement is
the new "command-string" type, and special-syntax functions
to make more use of it.

The new colon special monadic function consumes the remaining
subexpression's code representation in an array. Thus

f<:x+y

Sets f to the function x+y. f may be called as a procedure,
where x and y refer to global variables with the semicolon
(execute operator)

x<2
y<3
;f
5

Or, it may be called functionally, where x and y refer to
local arguments with the double-quote function.

2"f3
5

Or, a monadic function, using only the y argument may be
called with the single-quote function.

g<:y*2
'g3
9

The quote and double-quote functions also accept (as special
syntax) a parenthesized expression in place of the variable
(or other expression yielding the command-string-type array).
This expression may use x and y as arguments as with a
"named" function.

'(y*2)3
9

And this presents enough to define recursive functions,
like Fibonacci:

f<:;(y>1){(<:1);<:('fy-1)+'fy-2

Where the brace { is the "from" function, or [index]array,
and here the index is a Boolean zero or one which indexes
two expressions, :1 and :('fy-1)+'fy-2. These are boxed
with angle-bracket < so they can be combined into a
single array with semicolon ; to be selected from.

The interpreter also defines the variable a to contain
a boxed-array of command-string arrays which represent
the argv strings passed to the program, allowing inca
to access external data files via shell `cat ...` expansion.

The C code is getting pretty gawdoffal, but the language
itself is proving to be lots of fun to play with. YMMV.