0racle

Just an exploration of parsing this days input without regex.

Given the following code

c =. Parse;._2 fread 'input'

echo +/ (* #\) 12 13 14 *./@:>:"1 c
echo +/ */"1 c

Here's a rundown of definitions in my .jprofile.ijs, which get loaded in all J sessions.

Some of these are so simple they don't need names, but sometimes I just put things in here so I don't forget how to spell them.

Not all the functions are the most efficient, they're just there for playing with data. Often in a script, I will copy a function in, or re-write one that is more specific to the given problem domain.

Names

Alphanumerics

For most languages, I will have a "shebang" line at the top.

The shebang could be #!/usr/bin/env python3, but it could just as easily be -- !/usr/bin/env runhaskell or // !cargo run

This function reads everthing after the ! and uses that command to run the curent file

function! RunBang()
    if (&modified)
        :write

	if exists('b:current_syntax')\|fini\|en
	sy clear\|sy case match \|sy sync fromstart \|if&l:syn==#'k'\|setl com=:/ isk=a-z,A-Z,48-57 \|en
	" sy clear\|sy case match \|sy sync fromstart \|if&l:syn==#'k'\|en
	sy match k_e /\i\+\\|\S/
	sy match k_s /\(`\(\I\i\>\\|:[A-Za-z0-9.:/]\)\=\)\+/ nextgroup=@k_vw \|hi link k_s constant
	sy match k_w /[\\\/']:\=/ nextgroup=k_w contained \|hi link k_w operator
	sy match k_c1 /.\+/ contained \|hi link k_c1 special
	sy match k_c0 /\\\(\w\+\\|\\\\|$\)/ nextgroup=k_c1 \|hi link k_c0 statement
	sy match k_c0 /\\[tw]\>\(:\d\+\)\=/
	sy match k_e /"/ nextgroup=k_es \|hi link k_e error

	┌───┬───┐
	│abc│def│
	└───┴───┘
	e300000000000000
	2000000000000000
	0200000000000000
	0100000000000000
	0200000000000000
	3800000000000000
	6800000000000000

	//!/usr/bin/env node

	var ffi = require('ffi-napi');

	const BIN = '/opt/j904/bin';
	const LIB = `${BIN}/libj.so`;
	const PRO = `${BIN}/profile.ijs`;

	var libj = ffi.Library(LIB, {
	'JInit': [ 'pointer', [ ] ],

	sub infix:<p>($a, $b) is assoc<left> { $a + $b }
	sub infix:<t>($a, $b) is assoc<left> { $a * $b }

	for $=finish.lines -> $line {
	say $line.trans('+*' => 'pt').&EVAL;
	}

	=finish
	2 * 3 + (4 * 5)

	Parse =. (' ' joinstring ])@((3 1 0 { ])`(6 4 1 { ])@.(5 < #@]))@;:
	<@Parse;._2 'x-' rplc~ fread 'input'

	NB. or

	Parse =. (' ' joinstring \|.@}. , {.)@('rect\|row\|column\|\d+'&rxall)
	<@Parse"1 'm' fread 'input'

	Parse =. +/\@;@(<@(".@}. # 0j1 ^ 'RDLU' i. {.);._2)@,&','

	w =. Parse;._2 fread 'input'

	echo <./ +/@:\|@+. isects =. (e. # [)/ w
	echo <./ +/ >: i.&isects"1 w