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@dylanrenwick
Last active November 26, 2018 16:04
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Sum-It parser
function lex(code) {
code = code.split('\n');
code = {
src: code,
height: code.length,
width: 0
}
code.src = code.src.map(line => { code.width = Math.max(code.width, line.length); return line.split(''); });
code.src = code.src.map(line => { while(line.length < code.width) line.push(' '); return line; });
dbg(code);
ip = {
x: 0,
y: code.height - 1,
get: () => code.src[ip.y][ip.x],
climb: () => { ip.x++; ip.y--; },
fall: () => { ip.x++; ip.y++; },
peek: (down) => {
let peekX = (ip.x + 1);
let peekY = (ip.y + ((down) ? 1 : -1));
dbg('Peeking at [' + peekX + ', ' + peekY + ']');
if (peekX < 0 || peekY < 0 || peekX >= code.width || peekY >= code.height) {
dbg('Out of bounds peek, returning null');
return null;
}
let peeked = code.src[peekY][peekX];
dbg('Found ' + peeked);
return peeked;
},
text: () => '[' + ip.x + ', ' + ip.y + ']'
};
dbg(ip);
dbg(ip.text());
if (ip.get() !== '/') {
return lexError(ip, code, 'Expected entry point but found ' + ip.get());
}
function getSize(height) {
dbg('Getting size of ' + height);
let size = 0;
while(--height) {
size += height * 2;
}
dbg('Size is ' + size);
return size;
}
function getMtHeight(ip, code, offset) {
dbg('Getting mt starting at ' + ip.text() + ' with offset ' + offset);
let mtHeight = offset + 1;
while(ip.peek() === '/') {
ip.climb();
mtHeight++;
dbg(ip.text());
if (ip.y === 0) break;
}
ip.x++;
dbg(ip.text());
if (ip.get() !== '\\') {
return lexError(ip, code, 'Expected peak but found `' + ip.get() + "'");
}
dbg('Starting descent from peak at ' + ip.text());
let otherSide = 1
while(ip.peek(true) === '\\') {
ip.fall();
otherSide++;
if (ip.y === code.height - 1) break;
}
let extraOffset = 0;
if (ip.peek(true) === '/') {
otherSide++;
extraOffset++;
}
while(ip.get() !== '/' && ip.x++ < code.width) { }
let heightDiff = mtHeight - otherSide;
let mtSize = 0;
if (heightDiff < 0) {
return lexError(ip, code, 'Mountain other side is longer than main side!\n\tMain side is ' + mtHeight + ' (with ' + offset + ' offset), but other side is ' + otherSide);
} else if (heightDiff === 0) {
mtSize = getSize(mtHeight);
} else {
mtSize = getSize(otherSide) + (otherSide * heightDiff);
}
return [mtSize, heightDiff + extraOffset];
}
let ast = [];
let offset = 0;
while(ip.x < code.width) {
size = getMtHeight(ip, code, offset);
if (!size) return false;
dbg('Got size ' + size[0] + ' and offset ' + size[1]);
offset = size[1];
ast.push(size[0]);
}
return ast;
}
class StackyTape extends Array {
constructor() { super(); }
peek() { return this[this.length - 1]; }
rot(back) { back ? this.rotBack() : this.rotForward() }
rotBack() { this.push(this.shift()) }
rotForward() { this.unshift(this.pop()) }
toString() { return JSON.stringify(this); }
}
function parse(ast) {
stackyTape = new StackyTape();
var printed = false;
function getNextVal(codes) {
let val = codes.shift();
if (val == undefined) val = 0;
return val;
}
function safePop(data, def) {
let v = data.pop();
if (v === undefined) v = def;
return v;
}
function getDiadic(data, codes) {
let val = getNextVal(codes);
let v = safePop(data, val);
dbg('Got v as ' + v + ' and val as ' + val);
return [v, val];
}
function applyOperator(a1, a2, op) {
return eval('' + a1 + op + a2);
}
function operatorOp(data, codes, op) {
let vals = getDiadic(data, codes);
let result = applyOperator(vals[0], vals[1], op);
dbg('Result of ' + vals[0] + op + vals[1] + ' is ' + result);
return result;
}
let opCodes = [
// 00: no-op
(data, codes) => 0,
// 01: push
(data, codes) => data.push(codes.shift()),
// 02: add
(data, codes) => {
dbg('Adding');
let result = operatorOp(data, codes, '+');
data.push(result);
dbg(data);
},
// 03: sub
(data, codes) => {
dbg('Subtracting');
let result = operatorOp(data, codes, '-');
data.push(result);
dbg(data);
},
// 04: mul
(data, codes) => {
dbg('Multiplying');
let result = operatorOp(data, codes, '*');
data.push(result);
dbg(data);
},
// 05: div
(data, codes) => {
dbg('Dividing');
let result = operatorOp(data, codes, '/');
data.push(result);
dbg(data);
},
// 06: print
(data, codes) => { printed = true; process.stdout.write(String.fromCharCode(safePop(data, 0) % 127)) },
// 07: mod
(data, codes) => {
dbg('Modulusing');
let result = operatorOp(data, codes, '%');
data.push(result);
dbg(data);
},
// 08: pow
(data, codes) => {
dbg('Powering');
let result = operatorOp(data, codes, '**');
data.push(result);
dbg(data);
},
// 09: no-op
(data, codes) => 0,
// 10: dupe
(data, codes) => data.push(safePop(data, 0)),
// 11: no-op
(data, codes) => 0,
// 12: rot
(data, codes) => data.rot(),
];
while(ast.length) {
let code = ast.shift();
dbg('StackyTape is');
dbg(stackyTape);
dbg('and code to execute is ' + code);
dbg(opCodes[code]);
opCodes[code](stackyTape, ast);
}
dbg('StackyTape is');
dbg(stackyTape);
if (!printed) console.log(JSON.stringify(stackyTape));
}
function lexError(ip, code, msg) {
process.stderr.write(' ' + ' '.repeat(ip.x) + 'v' + (ip.x < code.width ? ' '.repeat(code.width - ip.x - 1) : '') + ' \n');
process.stderr.write(' ┏' + '━'.repeat(code.width) + '┓ \n');
for(y = 0; y < code.height; y++) {
process.stderr.write((y == ip.y ? '>' : ' ') + ' ┃');
for(x = 0; x < code.width; x++) {
process.stderr.write(code.src[y][x]);
}
process.stderr.write('┃ ' + (y == ip.y ? '<' : ' ') + '\n');
}
process.stderr.write(' ┗' + '━'.repeat(code.width) + '┛ \n');
process.stderr.write(' ' + ' '.repeat(ip.x) + '^' + (ip.x < code.width ? ' '.repeat(code.width - ip.x - 1) : '') + ' \n');
process.stderr.write(ip.text() + ' ' + msg);
return false;
}
function dbg(msg) {
if (typeof(msg) === 'object' || typeof(msg) === 'array') msg = JSON.stringify(msg);
if (typeof(msg) !== 'string') msg = msg.toString();
if (debug) console.log('[dbg]', msg);
}
let rawCode = process.argv[2];
if (!rawCode) { process.stderr.write('No code was given!'); process.exit(1); }
let dI = 3;
if (rawCode === '-f') {
dI++;
const fs = require('fs');
if (!process.argv[3]) { process.stderr.write('No file path was given!'); process.exit(2); }
try {
rawCode = fs.readFileSync(process.argv[3]);
} catch (e) {
process.stderr.write('Could not read file!\n');
process.stderr.write(e.message);
process.exit(3);
}
}
const debug = process.argv[dI] && process.argv[dI] == '-v';
//rawCode = rawCode.substring(1, rawCode.length - 1);
let ast = lex(rawCode);
if (!ast) process.exit(4);
dbg('Lexing done, AST is: ' + JSON.stringify(ast));
dbg('='.repeat(21));
dbg(' *' + ' '.repeat(17) + '* ');
dbg(' * Beginning parse * ');
dbg(' *' + ' '.repeat(17) + '* ');
dbg('='.repeat(21));
parse(ast);
@dylanrenwick
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dylanrenwick commented Nov 24, 2018

Sum-It

Sum-It is a mountain-range themed esoteric language, with a parser written in Node.js

Running

Run with node sum-it.js -f filename-goes-here

Writing

Code is stylized as ASCII art mountains, like so:

  /\
 /  \
/    \

Mountains are tokenized as an integer opcode, depending on their size (the number of characters beneath the surface of the mountain)
In the example above, the mountain has a total size of 6, counted as such:

  /\
 /##\
/####\

Any characters that do not directly make up the structure of the mountain's surface are ignored, and in most cases, slashes outside of mountains are fine too, however if they are too close to a base, peak or transition, they may confuse the tokenizer.

Overlapping mountains

In the case of 2 overlapping mountains, the right mountain takes priority, and "slices" the left mountain. For example:

      /\
  /\ /  \
 /  /    \
/  /      \

This would be counted as a 4, then a 10, like so:

      /\
  /\ /@@\
 /##/@@@@\
/##/@@@@@@\

Note that, for golfing purposes, it is possible to slightly reduce bytecount by overlapping the last char of a mountain with the first char of the next mountain, with no change in functionality. For example:

 /\  /\
/##\/@@\

Can be slghtly shortened to:

 /\ /\
/##/@@\

As this does not actually change the "size" of either mountain, the functionality is still the same

Opcode reference:

In this context, n refers to the next data value (See Data values above)

0 - No-Op
1 - Push n to the stack
2 - Sum n and the top item of the stack
    Monadic (Empty Stack) behaviour: Push n + n to the stack
3 - Subtract n from the top item of the stack
    Monadic (Empty Stack) behaviour: Push 0 to the stack
4 - Multiply n with the top item of the stack
    Monadic (Empty Stack) behaviour: Push n * n to the stack
5 - Divide the top item of the stack by n
    Monadic (Empty Stack) behaviour: Push 1 to the stack
6 - Pop from stack and print %127 as ASCII
7 - Modulo the top item of the stack with n
    Monadic (Empty Stack) behaviour: Push n to the stack
8 - Raise the top item of the stack to the power of n
    Monadic (Empty Stack) behaviour: Push n ** n to the stack
9 - No-Op
10 - Duplicate the top item of the stack
11 - No-Op
12 - Move the top item of the stack to the bottom of the stack

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