Develop Reference

isset equivalent in javascript to find palindrome

I created a script in PHP to find a palindrome, but when I try to do the same in JavaScript, then it is not working as expected. It's not just a matter of checking if the string that is reversed matches, but any order of the string has to be checked as well.
In other words, "mom" should return as true, "mmo" should return as true, "omm" should return as true, etc..., which is what the PHP script does, but the JS script below doesn't even work for the first iteration for the string "mom"
The following is the PHP script:
<?php
function is_palindrom($str) {
$str_array = str_split($str);
$count = array();
foreach ($str_array as $key) {
if(isset($count[$key])) {
$count[$key]++;
} else {
$count[$key] = 1;
}
}
$odd_counter = 0;
foreach ($count as $key => $val) {
if(($val % 2) == 1) {
$odd_counter++;
}
}
return $odd_counter <= 1;
}
echo is_palindrom('mom') ? "true" : "false";
The following is what I have tried in JS:
var count = [];
var strArr = [];
var oddCounter = 0;
var foreach_1 = function(item, index) {
console.log("count[index]: " + count[index]);
if (typeof count[index] !== "undefined") {
count[index]++;
} else {
count[index] = 1;
}
};
var foreach_2 = function(item, index) {
console.log("item: " + item + " item % 2: " + eval(item % 2));
if (eval(item % 2) == 1) {
oddCounter++;
}
console.log("oddCounter: " + oddCounter);
return oddCounter <= 1;
};
var isPalindrom = function(str) {
strArr = str.split("");
console.log(strArr);
strArr.forEach(foreach_1);
console.log(count);
count.forEach(foreach_2);
};
I believe it is failing where I try to replicate isset in javascript, with the following code:
if (typeof count[index] !== "undefined") {
As a result, I have tried to write my own isset function, but still the same result, it is not working:
var isset = function(obj) {
if (typeof obj === "undefined" || obj === null) {
return false;
} else {
return true;
}
};
With the following function being called:
if (isset(count[index])) {
count[index]++;
} else {
count[index] = 1;
}
As usual, any help would be appreciated and thanks in advance
BTW, it's killing me that I cannot remember the word for several revisions or iterations of something - I know that it starts with "re"

My attempt:
let p1 = `No 'x' in Nixon.`
let p2 = `Was it a car or a cat I saw?`
let p3 = `A man, a plan, a canal, Panama!`
function is_palindrome (str) {
const normalize = str => str.replace(/[.,:;`'"!?\/#$%\^&\*{}=\-_~()\s]/g, '').toLowerCase()
const reverse = str => [...str].reverse().join('')
return normalize(str) === reverse(normalize(str))
? true
: false
}
console.log(is_palindrome(p1))
console.log(is_palindrome(p2))
console.log(is_palindrome(p3))

First, thank you for all the comments.
Second, I ran a var_dump on the count array in the PHP file and this was the result:
array (size=2)
'm' => int 2
'o' => int 1
Which lead me to understand that count in js has to be an object for this work and I would have to create indexes of the object, depending on the string entered.
One thing lead to another and a complete re-write, but it works, along with a spell checker - see link at the bottom for complete code:
var count = {};
var strArr = [];
var oddCounter = 0;
var objKeys = [];
var splitString;
var reverseArray;
var joinArray;
var url = "test-spelling.php";
var someRes = "";
var mForN = function(obj, strArr) {
for (var y = 0; y < strArr.length; y++) {
// console.log("obj[strArr[" + y + "]]: " + obj[strArr[y]]);
if (isset(obj[strArr[y]])) {
obj[strArr[y]]++;
} else {
obj[strArr[y]] = 1;
}
}
return obj;
};
var mForN_2 = function(obj, objKeys) {
for (var z = 0; z < objKeys.length; z++) {
/* console.log(
"obj[objKeys[z]]: " +
obj[objKeys[z]] +
" obj[objKeys[z]] % 2: " +
eval(obj[objKeys[z]] % 2)
); */
if (eval(obj[objKeys[z]] % 2) == 1) {
oddCounter++;
}
// console.log("oddCounter: " + oddCounter);
}
return oddCounter <= 1;
};
var isset = function(obj) {
if (typeof obj === "undefined" || obj === null) {
return false;
} else {
return true;
}
};
var isPalindrom = function(str) {
// reverse original string
splitString = str.split("");
reverseArray = splitString.reverse();
joinArray = reverseArray.join("");
var checking = checkSpellingOfStr(str);
if (str == joinArray) {
strArr = str.split("");
// console.log("strArr: " + strArr);
objKeys = makeObjKeys(count, strArr);
// console.log("filled count before mForN: " + JSON.stringify(count));
// create array of keys in the count object
objKeys = Object.keys(count);
// console.log("objKeys: " + objKeys);
count = mForN(count, strArr);
// console.log("count after mForN: " + JSON.stringify(count));
return mForN_2(count, objKeys);
} else {
return 0;
}
};
var makeObjKeys = function(obj, arr) {
for (var x = 0; x < arr.length; x++) {
obj[arr[x]] = null;
}
return obj;
};
var checkSpellingOfStr = function(someStr) {
var formData = {
someWord: someStr
};
$.ajax({
type: "GET",
url: url,
data: formData,
success: function(result) {
if (!$.trim(result)) {
} else {
console.log(result);
$("#checkSpelling").html(result);
}
}
});
};
Start everything with the following call:
isPalindrom("mom") ? demoP.innerHTML = "is pal" : demoP.innerHTML = "is not pal";
In my example, I have a form and I listen for a button click as follows:
var palindromeTxt = document.getElementById("palindromeTxt").value;
var btn = document.getElementById("button");
btn.addEventListener("click", function (event) {
isPalindrom(palindromeTxt) ? demoP.innerHTML = "is pal" : demoP.innerHTML = "is not pal";
});
The following is the php for spell check:
<?php
error_reporting(E_ALL);
ini_set('display_errors', 1);
if(!empty($_REQUEST['someWord']))
{
$someWord = $_REQUEST['someWord'];
}
$pspell_link = pspell_new("en");
if (pspell_check($pspell_link, $someWord)) {
echo trim($someWord) . " is a recognized word in the English language";
} else {
echo "Your word is either misspelled or that is not a recognized word";
}
You will need pspell installed on your server, as well as adding extension=pspell.so to your php.ini
This is what I did, to get it running locally on my mac:
cd /Users/username/Downloads/php-5.6.2/ext/pspell
/usr/local/bin/phpize
./configure --with-php-config=/usr/local/php5-5.6.2-20141102-094039/bin/php-config --with-pspell=/opt/local/
make
cp ./modules/* /usr/local/php5-5.6.2-20141102-094039/lib/php/extensions/no-debug-non-zts-20131226
sudo apachectl restart
check your phpinfo file and you should see the following:
pspell
PSpell Support enabled
Live example

then not working as expected in JS promise

I'm trying to extract text from a pdf and then return a number that represents how many pages of the pdf are matched by a regex that I define.
My problem is that, rather than periodically checking whether or not the text of a single page is part of the match, my function divides the pieces up into smaller sections than pages. Count is meant to increment only after an entire page has been read.
getnopages: function(){
var fulltext = ""
var partialmatch;
var somerx = /something/
return pdfjs.getDocument(data).then(function(pdf) {
var pages = [];
pageNumbers = [];
for (var i = 0; i <= 6; i++) {
pages.push(i);
}
var found = false;
var count = 1;
return Promise.all(pages.map(function(pageNumber) {
pageNumbers.push(pageNumber);
return pdf.getPage(pageNumber + 1).then(function(page)
return page.getTextContent().then(function(textContent) {
return textContent.items.map(function(item) {
fulltext+=item.str+'&&&';
return item.str;
}).join('&&&');
});
}).then(function(){
count++;
console.log('the count is ' + count)
var partialmatch;
try {
partialmatch = fulltext.match(somerx)[0]
console.log('the match: ' + partialmatch)
var full = fulltext.slice(0, fulltext.length-3)
console.log('the full text ' + full)
if (fulltext && partialmatch!==full && !found){
found = true;
console.log('now we found our number: ' + count) // this finds where the full text differs from the partial text but returns a number too large to be a page number
}
}
catch(e){
console.log(e)
}
});
}));
}
Can anyone help me figure out how to rewrite this so that count is incrementing page numbers correctly?

I don't really know where is the problem in your code but I just suggest you to avoid too many nestings with promises. You can reduce nesting by chaining your promise like below:
getnopages: function() {
var somerx = /something/
return pdfjs.getDocument(data).then(function(pdf) {
var pages = [];
pageNumbers = [];
for (var i = 0; i <= 6; i++) {
pages.push(i);
}
var found = false;
var count = 1;
var promises = pages.map(pageNumber => {
pageNumbers.push(pageNumber);
return pdf.getPage(pageNumber + 1).then(page => {
return page.getTextContent();
}).then(textContent => {
return textContent.items.map(item => {
fulltext += item.str +'&&&';
return item.str;
}).join('&&&');
});
});
return Promise.all(promises).then(() => {
...
});
});
}

creating a new array out of an object

I've created a JavaScript object to get the number of times a character repeats in a string:
function getFrequency(string) {
// var newValsArray =[];
var freq = {};
for (var i=0; i<string.length;i++) {
var character = string.charAt(i);
if (freq[character]) {
freq[character]++;
} else {
freq[character] = 1;
}
}
return freq;
}
Now, I'm trying to construct a new string composed of the keys & their properties (the letters) & numbers of times the letters repeat if the number (property) is more than one but I keep getting undefined and I don't know why:
function newString(freq){
var newValsArray = [];
for (var prop in freq) {
if (freq[prop]>1){
newValsArray.push(prop + freq[prop]);
}
else if (freq[prop] < 2){
newValsArray.push(prop);
}
}
return newValsArray;
}
I feel like my syntax is off or something... if anyone has any suggestions, I'd really appreciate it...

You aren't explicitly returning anything from newString(), so it will return undefined. It sounds like you want something like this:
return newValsArray.join('');
at the end of newString() to construct an actual string (instead of returning an array). With that change, newString(getFrequency("Hello there") will return 'He3l2o thr'.

function getFrequency(string) {
// var newValsArray =[];
var freq = {};
for (var i = 0; i < string.length; i++) {
var character = string.charAt(i);
if (freq[character]) {
freq[character] ++;
} else {
freq[character] = 1;
}
}
return freq;
}
function newString(freq) {
var newValsArray = [];
for (var prop in freq) {
if (freq[prop] > 1) {
newValsArray.push(prop + freq[prop]);
} else if (freq[prop] < 2) {
newValsArray.push(prop);
}
}
return newValsArray.join("");
}
var mystring = "Here are some letters to see if we have any freq matches and so on.";
var results = newString(getFrequency(mystring));
var elem = document.getElementById("results");
elem.innerHTML = results;
<div id="results"></div>

You are not returning anything from the newString function. Add return newString; as the last line of the newString function. Adding that line does result in something being returned, though I can't tell if it is what you expected.
var text = "asdfjhwqe fj asdj qwe hlsad f jasdfj asdf alhwe sajfdhsadfjhwejr";
var myFreq = getFrequency(text);
show(myFreq);
var myNewValsArray = newString(myFreq);
show(myNewValsArray);
function getFrequency(string) {
// var newValsArray =[];
var freq = {};
for (var i=0; i<string.length;i++) {
var character = string.charAt(i);
if (freq[character]) {
freq[character]++;
} else {
freq[character] = 1;
}
}
return freq;
}
function newString(freq){
var newValsArray = [];
for (var prop in freq) {
if (freq[prop]>1){
newValsArray.push(prop + freq[prop]);
}
else if (freq[prop] < 2){
newValsArray.push(prop);
}
}
return newValsArray; // ******** ADD THIS LINE
}
function show(msg) {
document.write("<pre>" + JSON.stringify(msg, null, 2) + "</pre>");
}

Convert Indented Text List to HTML List (jQuery)

I am attempting to create a jQuery script which will convert an indented text list of arbitrary length and depth into a properly formatted HTML list. The lists on which I will be running this script are simple tree structures for directories. Within the tree structures, folders are denoted by a semicolon following the folder name (and files have no ending punctuation). Given this, I would like to attach a <span class="folder"></span> or <span class="file"></span> to the lines as appropriate.
I've found it to be fairly easy to generate most of the structure, but I cannot seem to get the recursion (which I suspect will be necessary) down to ensure that the tags are properly nested. The page on which this will be implemented will include the most recent (i.e., 3.0.3) version of Bootstrap, so feel free to use any of its functionality. I have about two dozen (generally abortive) fragments of code which I've tried or which I'm currently attempting to tweak to produce the desired result. Instead of posting a mass of (likely unhelpful) code, I've created a JSFiddle with the basic form which will be used for input/output, a bit of jQuery, and an example list and some external libraries loaded.
Any help or suggestions will be greatly appreciated.

Try this. I copied it to your fiddle and it seems to work.
var indentedToHtmlList = function indentedToHtmlList (text, indentChar, folderChar, listType, showIcons) {
indentChar = indentChar || '\t';
folderChar = folderChar || ':';
listType = listType || 'ul';
showIcons = !!showIcons;
var lastDepth,
lines = text.split(/\r?\n/),
output = '<' + listType + '>\n',
depthCounter = new RegExp('^(' + indentChar + '*)(.*)');
for (var i = 0; i < lines.length; i++) {
var splitted = lines[i].match(depthCounter),
indentStr = splitted[1],
fileName = splitted[2],
currentDepth = (indentStr === undefined) ? 0 : (indentStr.length / indentChar.length),
isFolder = (fileName.charAt(fileName.length - 1) === folderChar);
if (isFolder) {
fileName = fileName.substring(0, fileName.length -1);
}
if (lastDepth === currentDepth) {
output += '</li>\n';
} else if (lastDepth > currentDepth) {
while (lastDepth > currentDepth) {
output += '</li>\n</' + listType + '>\n</li>\n';
lastDepth--;
}
} else if (lastDepth < currentDepth) {
output += '\n<' + listType + '>\n';
}
output += '<li>';
if (showIcons) {
output += '<span class=" glyphicon glyphicon-' +
(isFolder ? 'folder-open' : 'file') +
'"></span> ';
}
output += fileName;
lastDepth = currentDepth;
}
while (lastDepth >= 0) {
output += '\n</li>\n</' + listType + '>';
lastDepth--;
}
return output;
};

You could use spans and classes to denote files and folders, but you should consider using ul and li elements, they were built for that.
The whole list should be enclosed within an ul element. Each entry on the top level list should create an li element inside of the main element. If the element is a folder, then it should also append another ul. This is where you'll need recursion to allow proper nesting.
However, if you intend to use indentation (no pun indented) the tab and or whitespace parsing is a problem by itself which I'm not solving in this answer. For the sake of this example, I'll just pretend you have a magic function that turns text into a parsed list called MyList, and that files that belong to a folder are whatever lies after the first semicolon of each list element.
var turnTextIntoList=function(AText) {
//magic stuff;
return SomeList;
};
var populateList=function(AList) {
var mainelement=jQuery('<ul></ul>');
for(element in AList) {
var the_li=jQuery('<li></li>');
if(element.indexOf(';')!=-1) {
the_li.append('<span class="file">'+element+'</span>');
} else {
var thefolder=element.split(';')
the_li.append('<span class="folder">'+thefolder[0]+'</span>');
the_li.append(populateList(turnTextIntoList(thefolder[1])));
}
mainelement.append(the_li);
}
return mainelement;
};
var MyList=turnTextIntoList(MyText);
jQuery('#targetdiv').append(populateList(MyList));
See, the recursion part is where you do
the_li.append(populateList(turnTextIntoList(thefolder[1])));
which will keep drilling into nesting levels until it reaches a file so it can start its way back.

It appears that someone already created a script which does this. Unfortunately, that script is in CoffeeScript, not JavaScript. However, there are a number online converters which will convert from CoffeeScript to JavaScript. Thanks to #charlietfl who provided a link to a working converter, supra.
Here is the converted, working code:
var bind, blank, convert, index, li, lineToMap, linesToMaps, parse, parseTuples, ptAccum, runConvert, tabCount, ul, ulEnd;
convert = function(text) {
return parse(text.split('\n'));
};
li = function(t) {
var html;
html = "<li>" + t['line'] + "</li>";
ptAccum.push(html);
return html;
};
ul = function(t) {
return ptAccum.push("<ul>" + (li(t)));
};
ulEnd = function() {
return ptAccum.push("</ul>");
};
ptAccum = [];
index = 0;
parse = function(lines) {
var ts;
ts = linesToMaps(lines);
ptAccum = ["<ul>"];
index = 0;
parseTuples(ts, 0);
ulEnd();
return ptAccum.join("\n");
};
parseTuples = function(tuples, level) {
var stop, _p, _results;
stop = false;
_p = function() {
var curLevel, t;
t = tuples[index];
curLevel = t['level'];
index++;
if (curLevel === level) {
return li(t);
} else if (curLevel < level) {
index--;
return stop = true;
} else {
ul(t);
parseTuples(tuples, level + 1);
return ulEnd();
}
};
_results = [];
while (!stop && index < tuples.length) {
_results.push(_p());
}
return _results;
};
tabCount = function(line) {
var c, count, i, inc, isTab, tc;
tc = 0;
c = '\t';
count = 0;
if (line) {
count = line.length;
}
i = 0;
isTab = function() {
return c === '\t';
};
inc = function() {
c = line.charAt(i);
if (isTab()) {
tc++;
}
return i++;
};
while (isTab() && i < count) {
inc();
}
return tc;
};
lineToMap = function(line) {
return {
line: line,
level: tabCount(line)
};
};
blank = function(line) {
return !line || line.length === 0 || line.match(/^ *$/);
};
linesToMaps = function(lines) {
var line, _i, _len, _results;
_results = [];
for (_i = 0, _len = lines.length; _i < _len; _i++) {
line = lines[_i];
if (!(blank(line))) {
_results.push(lineToMap(line));
}
}
return _results;
};
runConvert = function() {
var result;
result = convert($('#textarea-plain-text').val());
$('#textarea-converted-text').val(result);
return $('#div-converted-text').html(result);
};
bind = function() {
return $('#list-conversion-button').click(runConvert);
};
$(bind);
JSFiddle

How to replace only first sequential occurences (fuzzymatch)?

I'm trying to write "fuzzy" match and I can't find a way to solve this problem:
Data in: makrusakkk, query: mrk, expected result: <b>m</b>ak<b>r</b>usa<b>k</b>kk.
RegExp: "makrusakkk".match(/(m).*?(r).*?(k)/i) returns ["makrusak", "m", "r", "k"].
So the question is: is there a way to get the expected result using RegExp?

I think using regular expression for such problem makes things just more complicated. The following string and loop based solution would lead to the result:
function fuzzySearch(query, input) {
var inds = patternMatches(query, input);
if(!inds) return input;
var result = input;
for(var i = inds.length - 1; i >= 0; i--) {
var index = inds[i];
result = result.substr(0,index) +
"<b>" + result[index] + "</b>" +
result.substr(index+1);
}
return result;
}
function patternMatches(query, input) {
if(query.length <= 0) {
return [];
} else if(query.length == 1) {
if(input[0] == query[0]) return [0];
else return [];
} else {
if(input[0] != query[0])
return false;
var inds = [0];
for(var i = 1; i < query.length; i++) {
var foundInd = input.indexOf(query[i], inds[i-1]);
if(foundInd < 0) {
return [];
} else {
inds.push(foundInd);
}
}
return inds;
}
}
var input = "makrusakkksd";
var query = "mrk";
console.log(fuzzySearch(query, input));
console.log(patternMatches(query, input));
Here's a live demo too: http://jsfiddle.net/sinairv/T2MF4/

Here you will need for:
function search_for_it(txt, arr){
for(i=0;i<arr.length;i++){
var reg = new RegExp(arr[i], "i");
txt = txt.replace(reg, "<b>"+arr[i]+"</b>");
}
return txt;
}
search_for_it("makrusakkk", ["m","r","k"]);
//return "<b>m</b>a<b>k</b><b>r</b>usakkk"
PS: Your expected result is incorrect. There is a k after the first a.

is there a way to get an expected result using RegExp?
There is.
"makrusakkk".replace(/(m)(.*?)(r)(.*?)(k)/i, '<b>$1</b>$2<b>$3</b>$4<b>$5</b>'​​​​​​​)

I feel vaguely dirty for this, but...regardless; here's one way to do it:
$('#s').keyup(
function(e) {
var w = e.which;
if (w == 8 || w == 46) {
return false;
}
var listElems = $('ul:first li'),
search = $(this).val().replace(/w+/g, ''),
r = search.split(''),
rString = [];
$.each(r, function(i, v) {
rString.push('(' + v + ')');
});
var reg = new RegExp(rString.join('(\\d|\\D)*'), 'gi');
listElems.each(
function() {
if (!$(this).attr('data-origtext')) {
$(this).attr('data-origtext', $(this).text());
}
$(this).html($(this).attr('data-origtext').replace(reg, '<b>$&</b>'));
});
});​
JS Fiddle demo.
It could, almost certainly, benefit from quite some simplification though.
References:
attr().
:first selector.
join().
keyup().
push().
RegExp().
replace().
split().
text().
val().