We Keep Coding

Minifying javascript via unicode

on dwitter.net i often see dweets that are encoded interestingly to minify the JS to character count.
for example https://www.dwitter.net/d/22372 (or https://www.dwitter.net/d/11506)
eval(unescape(escape`𮀮𩡯𫡴🐧𜡥𫐠𨐧𛁸𛡦𪑬𫁔𩑸𭀨𙱜𭐲𝠲𜀠𙰬𜰬𜠵𚐊𭀿𜀺𩀽𮀮𩱥𭁉𫑡𩱥𡁡𭁡𚀰𛀰𛁶🐳𝠬𭠩𛡤𨑴𨐊𩡯𬠨𨰮𭱩𩁴𪁼👷👩🐹𜰶𞱩𛐭𞰩𩐽𪐥𭠪𝠬𩁛𪐪𝀫𜱝🠵𜁼𯁸𛡦𪑬𫁒𩑣𭀨𦀽𩐫𩐯𜠪𤰨𭀭𪐯𭰩𚱷𛁩𛰳𛑥𚡃𚁴𛑘𛰹𞐩𚱥𚰵𜀬𞐬𪐼𜐿𭰺𞐩`.replace(/u../g,'')))
Now I understand how to decode this and read the javascript, it's pretty trivial
unescape(escape`𮀮𩡯𫡴🐧𜡥𫐠𨐧𛁸𛡦𪑬𫁔𩑸𭀨𙱜𭐲𝠲𜀠𙰬𜰬𜠵𚐊𭀿𜀺𩀽𮀮𩱥𭁉𫑡𩱥𡁡𭁡𚀰𛀰𛁶🐳𝠬𭠩𛡤𨑴𨐊𩡯𬠨𨰮𭱩𩁴𪁼👷👩🐹𜰶𞱩𛐭𞰩𩐽𪐥𭠪𝠬𩁛𪐪𝀫𜱝🠵𜁼𯁸𛡦𪑬𫁒𩑣𭀨𦀽𩐫𩐯𜠪𤰨𭀭𪐯𭰩𚱷𛁩𛰳𛑥𚡃𚁴𛑘𛰹𞐩𚱥𚰵𜀬𞐬𪐼𜐿𭰺𞐩`.replace(/u../g,''))
returns
x.font='2em a',x.fillText('\u2620 ',3,25)
t?0:d=x.getImageData(0,0,v=36,v).data
for(c.width|=w=i=936;i--;)e=i%v*6,d[i*4+3]>50||x.fillRect(X=e+e/2*S(t-i/w)+w,i/3-e*C(t-X/99)+e+50,9,i<1?w:9)
but what I don't understand is how to encode js like this.
I noticed there is an intermediary step in this process
running:
escape`𮀮𩡯𫡴🐧𜡥𫐠𨐧𛁸𛡦𪑬𫁔𩑸𭀨𙱜𭐲𝠲𜀠𙰬𜰬𜠵𚐊𭀿𜀺𩀽𮀮𩱥𭁉𫑡𩱥𡁡𭁡𚀰𛀰𛁶🐳𝠬𭠩𛡤𨑴𨐊𩡯𬠨𨰮𭱩𩁴𪁼👷👩🐹𜰶𞱩𛐭𞰩𩐽𪐥𭠪𝠬𩁛𪐪𝀫𜱝🠵𜁼𯁸𛡦𪑬𫁒𩑣𭀨𦀽𩐫𩐯𜠪𤰨𭀭𪐯𭰩𚱷𛁩𛰳𛑥𚡃𚁴𛑘𛰹𞐩𚱥𚰵𜀬𞐬𪐼𜐿𭰺𞐩`
returns
%uD878%uDC2E%uD866%uDC6F%uD86E%uDC74%uD83D%uDC27%uD832%uDC65%uD86D%uDC20%uD861%uDC27%uD82C%uDC78%uD82E%uDC66%uD869%uDC6C%uD86C%uDC54%uD865%uDC78%uD874%uDC28%uD827%uDC5C%uD875%uDC32%uD836%uDC32%uD830%uDC20%uD827%uDC2C%uD833%uDC2C%uD832%uDC35%uD829%uDC0A%uD874%uDC3F%uD830%uDC3A%uD864%uDC3D%uD878%uDC2E%uD867%uDC65%uD874%uDC49%uD86D%uDC61%uD867%uDC65%uD844%uDC61%uD874%uDC61%uD828%uDC30%uD82C%uDC30%uD82C%uDC76%uD83D%uDC33%uD836%uDC2C%uD876%uDC29%uD82E%uDC64%uD861%uDC74%uD861%uDC0A%uD866%uDC6F%uD872%uDC28%uD863%uDC2E%uD877%uDC69%uD864%uDC74%uD868%uDC7C%uD83D%uDC77%uD83D%uDC69%uD83D%uDC39%uD833%uDC36%uD83B%uDC69%uD82D%uDC2D%uD83B%uDC29%uD865%uDC3D%uD869%uDC25%uD876%uDC2A%uD836%uDC2C%uD864%uDC5B%uD869%uDC2A%uD834%uDC2B%uD833%uDC5D%uD83E%uDC35%uD830%uDC7C%uD87C%uDC78%uD82E%uDC66%uD869%uDC6C%uD86C%uDC52%uD865%uDC63%uD874%uDC28%uD858%uDC3D%uD865%uDC2B%uD865%uDC2F%uD832%uDC2A%uD853%uDC28%uD874%uDC2D%uD869%uDC2F%uD877%uDC29%uD82B%uDC77%uD82C%uDC69%uD82F%uDC33%uD82D%uDC65%uD82A%uDC43%uD828%uDC74%uD82D%uDC58%uD82F%uDC39%uD839%uDC29%uD82B%uDC65%uD82B%uDC35%uD830%uDC2C%uD839%uDC2C%uD869%uDC3C%uD831%uDC3F%uD877%uDC3A%uD839%uDC29
which then gets regex replaced with .replace(/u../g,''), but getting this string from minified javascript isn't easy for me.
simply running encodeURIComponent() or escape() doesn't get you quite there, though it gets you part of the way there.
So how do I get the string of my javascript converted into a string containing %uD then the character code for each?

I am also on dwitter.
The code compressor actually began with a dweet (https://www.dwitter.net/d/23092).
It was made so people could add more bytes into their demos by going right up to 194 chars instead of having the limit of 140.
Note this does not reduce the byte size.
Even though this reduces the amount of characters, the size stays the same
There is also an uncompressor at https://www.dwitter.net/d/14246
The simplified code for this is a simple unpack function:
function unpack(strange_blocky_code) {
const index = code.toLowerCase().search(/eval\(unescape\(escape`/g)
if (index >= 0) {
const start = strange_blocky_code.slice(0, index)
const end = strange_blocky_code.slice(index)
const result = eval(end.slice(4))
if (result) return start + result // returns readable (but trivial) code
}
}
The simplified compressing code is:
function compress(readable_code) {
const value = [...readable_code.trim()]
let code = ''
for (let character of value) {
const char = character.charCodeAt(0)
if (char > 255) character = escape(character).replace(/%u/g, "\\u")
code += character
}
const compressed =
String.fromCharCode(...[...code.length % 2 ? code + ";" : code]
.map((item, index) =>
item.charCodeAt() | (index % 2 ? 0xDF00 : 0xDB00)
)
)
return `eval(unescape(escape\`${compressed}\`.replace(/u../g,'')))`
}
If you're looking for editors, these are two that I like to use:
https://greyhope.uk/Dweet-Runner/index.html made by GreyHope
https://dweetabase.3d2k.com/ made by Frank Force
I hope this helps at all.

how to add numbers with an infinite number of digits using column addition?

I am trying to develop the addition program using column addition in javascript, For e.g: 53,22 , we add numbers from the right 3+2 and 5+2 finally results in 75, the main problem is with large numbers i am trying to develop a program which can implement addition of large numbers.so that i don't get gibberish like 1.26E+9, when adding large numbers. i tried doing it by defining the code like below
function add(a,b)
{
return (Number(a) + Number(b)).toString();
}
console.log(add('58685486858601586', '8695758685'));
i am trying to get the added number without getting the gibberish like 5.8685496e+16

You can add them digit by digit.
function sumStrings(a, b) { // sum for any length
function carry(value, index) { // cash & carry
if (!value) { // no value no fun
return; // leave shop
}
this[index] = (this[index] || 0) + value; // add value
if (this[index] > 9) { // carry necessary?
carry.bind(this)(this[index] / 10 | 0, index + 1); // better know this & go on
this[index] %= 10; // remind me later
}
}
var array1 = a.split('').map(Number).reverse(), // split stuff and reverse
array2 = b.split('').map(Number).reverse(); // here as well
array1.forEach(carry, array2); // loop baby, shop every item
return array2.reverse().join(''); // return right ordered sum
}
document.write(sumStrings('58685486858601586', '8695758685') + '<br>');
document.write(sumStrings('999', '9') + '<br>');
document.write(sumStrings('9', '999') + '<br>');
document.write(sumStrings('1', '9999999999999999999999999999999999999999999999999999') + '<br>');

I would keep all values as numbers until done with all the calculations. When ready to display just format the numbers in any way you want. For example you could use toLocaleString.

There are several libraries for that
A good rule of thumb is to make sure you do research for libraries before you actually go ahead and create you're own proprietary implementation of it. Found three different libraries that all solve your issue
bignumber.js
decimal.js
big.js
Example
This is how to use all three of the libraries, BigNumber coming from the bignumber.js library, Decimal from decimal.js and Big from big.js
var bn1 = new BigNumber('58685486858601586');
var bn2 = new BigNumber('8695758685');
console.log(bn1.plus(bn2).toString());
bn1 = new Decimal('58685486858601586');
bn2 = new Decimal('8695758685');
console.log(bn1.plus(bn2).toString());
bn1 = new Big('58685486858601586');
bn2 = new Big('8695758685');
console.log(bn1.plus(bn2).toString());
The console's output is :
58685495554360271
58685495554360271
58685495554360271

Does JavaScript support array/list comprehensions like Python?

I'm practicing/studying both JavaScript and Python. I'm wondering if Javascript has the equivalence to this type of coding.
I'm basically trying to get an array from each individual integer from the string for practice purposes. I'm more proficient in Python than JavaScript
Python:
string = '1234-5'
forbidden = '-'
print([int(i) for i in str(string) if i not in forbidden])
Does Javascript have something similar for me to do above?

Update: Array comprehensions were removed from the standard. Quoting MDN:
The array comprehensions syntax is non-standard and removed starting with Firefox 58. For future-facing usages, consider using Array.prototype.map, Array.prototype.filter, arrow functions, and spread syntax.
See this answer for an example with Array.prototype.map:
let emails = people.map(({ email }) => email);
Original answer:
Yes, JavaScript will support array comprehensions in the upcoming EcmaScript version 7.
Here's an example.
var str = "1234-5";
var ignore = "-";
console.log([for (i of str) if (!ignore.includes(i)) i]);

Given the question's Python code
print([int(i) for i in str(string) if i not in forbidden])
this is the most direct translation to JavaScript (ES2015):
const string = '1234-5';
const forbidden = '-';
console.log([...string].filter(c => !forbidden.includes(c)).map(c => parseInt(c)));
// result: [ 1, 2, 3, 4, 5 ]
Here is a comparison of the Python and JavaScript code elements being used:
(Python -> Javascript):
print -> console.log
unpacking string to list -> spread operator
list comprehension 'if' -> Array.filter
list comprehension 'for' -> Array.map
substr in str? -> string.includes

Reading the code, I assume forbidden can have more than 1 character. I'm also assuming the output should be "12345"
var string = "12=34-5";
var forbidden = "=-";
console.log(string.split("").filter(function(str){
return forbidden.indexOf(str) < 0;
}).join(""))
If the output is "1" "2" "3" "4" "5" on separate lines
var string = "12=34-5";
var forbidden = "=-";
string.split("").forEach(function(str){
if (forbidden.indexOf(str) < 0) {
console.log(str);
}
});

Not directly, but it's not hard to replicate.
var string = "1234-5";
var forbidden = "-";
string.split("").filter(function(str){
if(forbidden.indexOf(str) < 0) {
return str;
}
}).forEach(function(letter) { console.log(letter);});
I guess more directly:
for(var i=0 ; i < str.length ; i++) {
if(forbidden.indexOf(str) < 0) {
console.log(str[i]);
}
}
But there's no built in way to filter in your for loop.

You could easily achieve this behavior using an application functor.
Array.prototype.ap = function(xs) {
return this.reduce((acc, f) => acc.concat(xs.map(f)), [])
}
const result = [x => x +1].ap([2])
console.log(result)

JavaScript no longer supports array comprehensions.
I too was looking for the JavaScript equivalent. Mozilla Developer's Network indicates that this functionality is no longer supported.
The preferred syntax is referenced in the aforementioned link.

For "completeness"-sake, here's a shorter regexp version.
var str = "1234-5";
var ignore = "-=";
console.log(str.replace(new RegExp(ignore.split("").join("|")), "").split(""));
EDIT: To make sure that RegExp does not "choke" on special characters, ignore can be implemented as regexp literal, instead of a string:
var str = "1234-5";
var ignore = /[\+=-]/;
console.log(str.replace(ignore, "").split(""));

It does have a poor mans version
const string = '1234-5'
const forbidden = '-'
print([int(i) for i in str(string) if i not in forbidden])
const result = string.split('').filter(char => char !== forbidden);
console.log(result)
In JS you can only iterate over single elements in array, so no extraction of multiple entries at a time like in Python.
For this particular case you should use a RegExp to filter the string though.

You could have a look at CoffeeScript.
CoffeeScript adds missing features to java-script and allows you to write cleaner, more readable code. https://coffeescript.org/#coffeescript-2
You write a .coffee file and the coffeScript-compiler compiles your coffee file into a JavaScript file. Because the translation into JavaScript happens by compiling, the script should not run any slower.
So your code would look like the following in coffee script:
string = '1234-5'
forbidden = '-'
alert(JSON.stringify(+i for i in string when i isnt forbidden))
Honestly, this is even easier to read then the python counterpart. And it compiles quickly to the fallowing JavaScript:
var forbidden, i, string;
string = '1234-5';
forbidden = '-';
alert(JSON.stringify((function() {
var j, len, results;
results = [];
for (j = 0, len = string.length; j < len; j++) {
i = string[j];
if (i !== forbidden) {
results.push(+i);
}
}
return results;
})()));
You don’t even need to install anything. On their website you can play around with it, and it will show you the translated JavaScript code.

Javascript doesn't need list comprehensions because the map and filter functions work better in the language compared to Python.
In Python:
[int(i) for i in '1234-5' if i != '-']
# is equivalent to the ugly
list(map(lambda _: int(_),filter(lambda _: _!='-','1234-5')))
# so we use list comprehensions
In Javascript, to me this is fine once you're familiar with the syntax:
[...'1234-5'].filter(_=> _!='-').map(_=> parseInt(_))

How do I convert String to Number according to locale (opposite of .toLocaleString)?

If I do:
var number = 3500;
alert(number.toLocaleString("hi-IN"));
I will get ३,५०० in Hindi.
But how can I convert it back to 3500.
I want something like:
var str='३,५००';
alert(str.toLocaleNumber("en-US"));
So, that it can give 3500.
Is it possible by javascript or jquery?

I think you are looking for something like:
https://github.com/jquery/globalize
Above link will take you to git project page. This is a js library contributed by Microsoft.
You should give it one try and try to use formt method of that plugin. If you want to study this plugin, here is the link for the same:
http://weblogs.asp.net/scottgu/jquery-globalization-plugin-from-microsoft
I hope this is what you are looking for and will resolve your problem soon. If it doesn't work, let me know.

Recently I've been struggling with the same problem of converting stringified number formatted in any locale back to the number.
I've got inspired by the solution implemented in NG Prime InputNumber component. They use Intl.NumberFormat.prototype.format() (which I recommend) to format the value to locale string, and then create set of RegExp expressions based on simple samples so they can cut off particular expressions from formatted string.
This solution can be simplified with using Intl.Numberformat.prototype.formatToParts(). This method returns information about grouping/decimal/currency and all the other separators used to format your value in particular locale, so you can easily clear them out of previously formatted string. It seems to be the easiest solution, that will cover all cases, but you must know in what locale the value has been previously formatted.
Why Ng Prime didn't go this way? I think its because Intl.Numberformat.prototype.formatToParts() does not support IE11, or perhaps there is something else I didn't notice.
A complete code example using this solution can be found here.

Unfortunately you will have to tackle the localisation manually. Inspired by this answer , I created a function that will manually replace the Hindi numbers:
function parseHindi(str) {
return Number(str.replace(/[०१२३४५६७८९]/g, function (d) {
return d.charCodeAt(0) - 2406;
}).replace(/[०१२३४५६७८९]/g, function (d) {
return d.charCodeAt(0) - 2415;
}));
}
alert(parseHindi("३५००"));
Fiddle here: http://jsfiddle.net/yyxgxav4/

You can try this out
function ConvertDigits(input, source, target) {
var systems = {
arabic: 48, english: 48, tamil: 3046, kannada: 3302, telugu: 3174, hindi: 2406,
malayalam: 3430, oriya: 2918, gurmukhi: 2662, nagari: 2534, gujarati: 2790,
},
output = [], offset = 0, zero = 0, nine = 0, char = 0;
source = source.toLowerCase();
target = target.toLowerCase();
if (!(source in systems && target in systems) || input == null || typeof input == "undefined" || typeof input == "object") {
return input;
}
input = input.toString();
offset = systems[target] - systems[source];
zero = systems[source];
nine = systems[source] + 9;
for (var i = 0 ; i < input.length; i++) {
var char = input.charCodeAt(i);
if (char >= zero && char <= nine) {
output.push(String.fromCharCode(char + offset));
} else {
output.push(input[i]);
}
}
return output.join("");
}
var res = ConvertDigits('१२३४५६७८९', 'hindi', 'english');
I got it from here
If you need a jquery thing then please try this link

Use the Globalize library.
Install it
npm install globalize cldr-data --save
then
var cldr = require("cldr-data");
var Globalize = require("globalize");
Globalize.load(cldr("supplemental/likelySubtags"));
Globalize.load(cldr("supplemental/numberingSystems"));
Globalize.load(cldr("supplemental/currencyData"));
//replace 'hi' with appropriate language tag
Globalize.load(cldr("main/hi/numbers"));
Globalize.load(cldr("main/hi/currencies"));
//You may replace the above locale-specific loads with the following line,
// which will load every type of CLDR language data for every available locale
// and may consume several hundred megs of memory!
//Use with caution.
//Globalize.load(cldr.all());
//Set the locale
//We use the extention u-nu-native to indicate that Devanagari and
// not Latin numerals should be used.
// '-u' means extension
// '-nu' means number
// '-native' means use native script
//Without -u-nu-native this example will not work
//See
// https://en.wikipedia.org/wiki/IETF_language_tag#Extension_U_.28Unicode_Locale.29
// for more details on the U language code extension
var hindiGlobalizer = Globalize('hi-IN-u-nu-native');
var parseHindiNumber = hindiGlobalizer.numberParser();
var formatHindiNumber = hindiGlobalizer.numberFormatter();
var formatRupeeCurrency = hindiGlobalizer.currencyFormatter("INR");
console.log(parseHindiNumber('३,५००')); //3500
console.log(formatHindiNumber(3500)); //३,५००
console.log(formatRupeeCurrency(3500)); //₹३,५००.००
https://github.com/codebling/globalize-example

A common scenario for this problem is to display a float number to the user and then want it back as a numerical value.
In that case, javascript has the number in the first place and looses it when formatting it for display. A simple workaround for the parsing is to store the real float value along with the formatted value:
var number = 3500;
div.innerHTML = number.toLocaleString("hi-IN");
div.dataset.value = number;
Then get it back by parsing the data attribute:
var number = parseFloat(div.dataset.value);
This is a Columbus's egg style answer. It works provided the problem is an egg.

var number = 3500;
var toLocaleString = number.toLocaleString("hi-IN")
var formatted = toLocaleString.replace(',','')
var converted = parseInt(formatted)

Letters to predefined numbers conversion in one window

)
I have searched high and low, but i can´t find what i need. Or i´m to stupid to get it right ;-)
I need a page with several input boxes where i can type some text, and then an output area below each input, that shows the text converted to some predefined numbers.
example:
input: abcde fghi æøå (i need all kinds of characters like .,/: etc.)
output: 064 065 066 067 068 032
So it needs to convert like this:
"a"="064 "
"b"="065 "
"space"="032 "
(and yes, each number in output needs to be separated, or a space added after each number)
I have tried some different cipher guides in both php and javascript, but can´t get it to work. I did do an Excel document that could do some of it, but it had a limited amount of characters it could convert, then it started behaving weird. So i thought maybe PHP was the answer!
Any help is very appreciated
/Rasmus

In the spirit of elclanrs deleted answer, and for posterity:
<script>
// Using standard for loop
function stringToCharcodes(s) {
var result = [];
function pad(n){ return (n<10? '00' : n<100? '0' : 0) + n;}
for (var i=0, iLen=s.length; i<iLen; i++) {
result.push(pad(s.charCodeAt(i)));
}
return result.join(' ');
}
// Using ES5 forEach
function stringToCharcodes2(s) {
var result = [];
function pad(n){ return (n<10? '00' : n<100? '0' : 0) + n;}
s.split('').forEach(function(a){result.push(pad(a.charCodeAt(0)))});
return result.join(' ');
}
</script>
<input onkeyup="document.getElementById('s0').innerHTML = stringToCharcodes(this.value);"><br>
<span id="s0"></span>
Edit
If you want a custom mapping, use an object (I've only included 2 characters, you can add as many as you want):
var mapChars = (function() {
var mapping = {'198':'019', '230':'018'};
return function (s) {
var c, result = [];
for (var i=0, iLen=s.length; i<iLen; i++) {
c = s.charCodeAt(i);
result.push(c in mapping? mapping[c] : c);
}
return result.join(' ');
}
}());
alert(mapChars('Ææ')); //
Using the character code for mapping seems to be a reasonable solution, using the actual character may be subject to different page character encoding.