Develop Reference

adding indicators into a string according to different case

I will receive an array of string-like below.
In each string, there may be three signs: $,%,* in the string
For example,
“I would $rather %be $happy, %if working in a chocolate factory”
“It is ok to play tennis”
“Tennis $is a good sport”
“AO is really *good sport”
However, there may be no signs in it, maybe only one sign in it.
There are only five cases in string,
1. no sign at all,
2. having $,% ;
3. having only $,
4 having only %,
5 having only *
If there is no sign, I don’t need to process it.
Otherwise, I need to process it and add an indicator to the left of the first sign that occurs in the sentence.
For example:
“I would ---dollorAndperSign—-$rather %be $happy, %if working in a chocolate factory”
“Tennis --dollorSign—-$is a good sport”
This is my idea code.
So, I need to decide if the string contains any sign. If there is no sign, I don’t need to process it.
texts.map((text) => {
if (text.includes("$") || text.includes("%") || text.includes("*")) {
//to get the index of signs
let indexOfdollar, indexOfper, indexOfStar;
indexOfdollar = text.indexOf("$");
indexOfper = text.indexOf("%");
indexOfStar = text.indexOf("*");
//return a completed process text
}
});
Question:
how do I know which index is the smallest one in order to locate the position of the first sign occurring in the text? Getting the smallest value may not be the correct approach coz there may be the case that I will get -1 from the above code?

I focussed only on the "get the smallest index" part of your question... Since you will be able to do what you want with it after.
You can have the indexOf() in an array, filter it to remove the -1 and then use Math.min() to get the smallest one.
Edited to output an object instead, which includes the first index and some booleans for the presence each char.
const texts = [
"I would $rather %be $happy, %if working in a chocolate factory",
"It is ok to play tennis",
"Tennis $is a good sport",
"AO is really *good sport"
]
const minIndexes = texts.map((text,i) => {
//to get the signs
const hasDollard = text.indexOf("$") >= 0
const hasPercent = text.indexOf("%") >= 0
const hasStar = text.indexOf("*") >= 0
//to get the first index
const indexes = [text.indexOf("$"), text.indexOf("%"), text.indexOf("*")].filter((index) => index >= 0)
if(!indexes.length){
return null
}
return {
index: Math.min( ...indexes),
hasDollard,
hasPercent,
hasStar
}
});
console.log(minIndexes)

const texts = [
"I would $rather %be $happy, %if working in a chocolate factory",
"It is ok to play tennis",
"Tennis $is a good sport",
"AO is really *good sport"
]
texts.forEach(text => {
let sighs = ["%","$","*"];
let chr = text.split('').find(t => sighs.find(s => s==t));
if (!chr)
return;
text = text.replace(chr, "---some text---" + chr);
console.log(text);
})

const data = ['I would $rather %be $happy, %if working in chocolate factory', 'It is ok to play tennis', 'Tennis $is a good sport', 'AO is really *good sport']
const replace = s => {
signs = { $: 'dollar', '%': 'per', '*': 'star' },
characters = Array.from(s, (c,i)=> '$%*'.includes(c)? c:'').join('')
headText = [...new Set(Array.from(characters))].map(c => signs[c]).join('|')
s.replace(/[\$\%\*]/, `--${text}--$&`);
}
const result = data.map(replace)

Looking for the easiest way to extract an unknown substring from within a string. (terms separated by slashes)

The initial string:
initString = '/digital/collection/music/bunch/of/other/stuff'
What I want: music
Specifically, I want any term (will never include slashes) that would come between collection/ and /bunch
How I'm going about it:
if(initString.includes('/digital/collection/')){
let slicedString = initString.slice(19); //results in 'music/bunch/of/other/stuff'
let indexOfSlash = slicedString.indexOf('/'); //results, in this case, to 5
let desiredString = slicedString.slice(0, indexOfSlash); //results in 'music'
}
Question:
How the heck do I accomplish this in javascript in a more elegant way?
I looked for something like an endIndexOf() that would replace my hardcoded .slice(19)
lastIndexOf() isn't what I'm looking for, because I want the index at the end of the first instance of my substring /digital/collection/
I'm looking to keep the number of lines down, and I couldn't find anything like a .getStringBetween('beginCutoff, endCutoff')
Thank you in advance!

your title says "index" but your example shows you wanting to return a string. If, in fact, you are wanting to return the string, try this:
if(initString.includes('/digital/collection/')) {
var components = initString.split('/');
return components[3];
}

If the path is always the same, and the field you want is the after the third /, then you can use split.
var initString = '/digital/collection/music/bunch/of/other/stuff';
var collection = initString.split("/")[2]; // third index
In the real world, you will want to check if the index exists first before using it.
var collections = initString.split("/");
var collection = "";
if (collections.length > 2) {
collection = collections[2];
}

You can use const desiredString = initString.slice(19, 24); if its always music you are looking for.

If you need to find the next path param that comes after '/digital/collection/' regardless where '/digital/collection/' lies in the path
first use split to get an path array
then use find to return the element whose 2 prior elements are digital and collection respectively
const initString = '/digital/collection/music/bunch/of/other/stuff'
const pathArray = initString.split('/')
const path = pathArray.length >= 3
? pathArray.find((elm, index)=> pathArray[index-2] === 'digital' && pathArray[index-1] === 'collection')
: 'path is too short'
console.log(path)

Think about this logically: the "end index" is just the "start index" plus the length of the substring, right? So... do that :)
const sub = '/digital/collection/';
const startIndex = initString.indexOf(sub);
if (startIndex >= 0) {
let desiredString = initString.substring(startIndex + sub.length);
}
That'll give you from the end of the substring to the end of the full string; you can always split at / and take index 0 to get just the first directory name form what remains.

You can also use regular expression for the purpose.
const initString = '/digital/collection/music/bunch/of/other/stuff';
const result = initString.match(/\/digital\/collection\/([a-zA-Z]+)\//)[1];
console.log(result);
The console output is:
music

If you know the initial string, and you have the part before the string you seek, then the following snippet returns you the string you seek. You need not calculate indices, or anything like that.
// getting the last index of searchString
// we should get: music
const initString = '/digital/collection/music/bunch/of/other/stuff'
const firstPart = '/digital/collection/'
const lastIndexOf = (s1, s2) => {
return s1.replace(s2, '').split('/')[0]
}
console.log(lastIndexOf(initString, firstPart))

Filtering ranges of letters in Javascript

I have to create a program that takes the first letter of a prompt, and if that letter is between a and k, then it has to produce a certain output, if it's between l and p another and so on. Is there a way to do this without writing every letter of the alphabet down? (sorry I'm a new coder)

I think you should try to solve the problem, before asking - so you can show what you've already tried.
I think the snippet below points you in the right direction - but it takes any character, not just letters. You need to get everything filtered out that's not a lower case letter.
// UI elements
const input = document.getElementById('input1')
const result = document.getElementById('result')
// input event
// only the first character is taken into account
input.addEventListener('input', function(e) {
// adding the characters of the input value to an array, and
// picking the 0th element (or '', if there's no 0th element)
const a = [...this.value][0] || ''
let ret = ''
if (a !== '') {
// lowercaseing letters, so it's easier to categorize them
ret = categorizeAlphabet(a.toLowerCase().charCodeAt(0))
} else {
ret = 'The input is empty'
}
// displaying the result
result.textContent = ret
})
// you could use this function to filter and categorize
// according to the problem ahead of you - and return the result
// to be displayed.
// In this example this function is rather simple, but
// you can build a more complex return value.
const categorizeAlphabet = (chCode) => {
return `This is the character code: ${chCode}`
}
<label>
First character counts:
<input type="text" id='input1'>
</label>
<h3 id="result">The input is empty</h3>

Get initials and full last name from a string containing names

Assume there are some strings containing names in different format (each line is a possible user input):
'Guilcher, G.M., Harvey, M. & Hand, J.P.'
'Ri Liesner, Peter Tom Collins, Michael Richards'
'Manco-Johnson M, Santagostino E, Ljung R.'
I need to transform those names to get the format Lastname ABC. So each surename should be transformed to its initial which are appended to the lastname.
The example should result in
Guilcher GM, Harvey M, Hand JP
Liesner R, Collins PT, Richards M
Manco-Johnson M, Santagostino E, Ljung R
The problem is the different (possible) input format. I think my attempts are not very smart, so I'm asking for
Some hints to optimize the transformation code
How do I put those in a single function at all? I think first of all I have to test which format the string has...??
So let me explain how far I tried to solve that:
First example string
In the first example there are initials followed by a dot. The dots should be removed and the comma between the name and the initals should be removed.
firstString
.replace('.', '')
.replace(' &', ', ')
I think I do need an regex to get the comma after the name and before the initials.
Second example string
In the second example the name should be splitted by space and the last element is handled as lastname:
const elm = secondString.split(/\s+/)
const lastname = elm[elm.length - 1]
const initials = elm.map((n,i) => {
if (i !== elm.length - 1) return capitalizeFirstLetter(n)
})
return lastname + ' ' + initals.join('')
...not very elegant
Third example string
The third example has the already the correct format - only the dot at the end has to be removed. So nothing else has to be done with that input.

It wouldn't be possible without calling multiple replace() methods. The steps in provided solution is as following:
Remove all dots in abbreviated names
Substitute lastname with firstname
Replace lastnames with their beginning letter
Remove unwanted characters
Demo:
var s = `Guilcher, G.M., Harvey, M. & Hand, J.P.
Ri Liesner, Peter Tom Collins, Michael Richards
Manco-Johnson M, Santagostino E, Ljung R.`
// Remove all dots in abbreviated names
var b = s.replace(/\b([A-Z])\./g, '$1')
// Substitute first names and lastnames
.replace(/([A-Z][\w-]+(?: +[A-Z][\w-]+)*) +([A-Z][\w-]+)\b/g, ($0, $1, $2) => {
// Replace full lastnames with their first letter
return $2 + " " + $1.replace(/\b([A-Z])\w+ */g, '$1');
})
// Remove unwanted preceding / following commas and ampersands
.replace(/(,) +([A-Z]+)\b *[,&]?/g, ' $2$1');
console.log(b);

Given your example data i would try to make guesses based on name part count = 2, since it is very hard to rely on any ,, & or \n - which means treat them all as ,.
Try this against your data and let me know of any use-cases where this fails because i am highly confident that this script will fail at some point with more data :)
let testString = "Guilcher, G.M., Harvey, M. & Hand, J.P.\nRi Liesner, Peter Tom Collins, Michael Richards\nManco-Johnson M, Santagostino E, Ljung R.";
const inputToArray = i => i
.replace(/\./g, "")
.replace(/[\n&]/g, ",")
.replace(/ ?, ?/g, ",")
.split(',');
const reducer = function(accumulator, value, index, array) {
let pos = accumulator.length - 1;
let names = value.split(' ');
if(names.length > 1) {
accumulator.push(names);
} else {
if(accumulator[pos].length > 1) accumulator[++pos] = [];
accumulator[pos].push(value);
}
return accumulator.filter(n => n.length > 0);
};
console.log(inputToArray(testString).reduce(reducer, [[]]));

Here's my approach. I tried to keep it short but complexity was surprisingly high to get the edge cases.
First I'm formatting the input, to replace & for ,, and removing ..
Then, I'm splitting the input by \n, then , and finally (spaces).
Next I'm processing the chunks. On each new segment (delimited by ,), I process the previous segment. I do this because I need to be sure that the current segment isn't an initial. If that's the case, I do my best to skip that inital-only segment and process the previous one. The previous one will have the correct initial and surname, as I have all the information I neeed.
I get the initial on the segment if there's one. This will be used on the start of the next segment to process the current one.
After finishing each line, I process again the last segment, as it wont be called otherwise.
I understand the complexity is high without using regexp, and probably would have been better to use a state machine to parse the input instead.
const isInitial = s => [...s].every(c => c === c.toUpperCase());
const generateInitial = arr => arr.reduce((a, c, i) => a + (i < arr.length - 1 ? c[0].toUpperCase() : ''), '');
const formatSegment = (words, initial) => {
if (!initial) {
initial = generateInitial(words);
}
const surname = words[words.length - 1];
return {initial, surname};
}
const doDisplay = x => x.map(x => x.surname + ' ' + x.initial).join(', ');
const doProcess = _ => {
const formatted = input.value.replace(/\./g, '').replace(/&/g, ',');
const chunks = formatted.split('\n').map(x => x.split(',').map(x => x.trim().split(' ')));
const peoples = [];
chunks.forEach(line => {
let lastSegment = null;
let lastInitial = null;
let lastInitialOnly = false;
line.forEach(segment => {
if (lastSegment) {
// if segment only contains an initial, it's the initial corresponding
// to the previous segment
const initialOnly = segment.length === 1 && isInitial(segment[0]);
if (initialOnly) {
lastInitial = segment[0];
}
// avoid processing last segments that were only initials
// this prevents adding a segment twice
if (!lastInitialOnly) {
// if segment isn't an initial, we need to generate an initial
// for the previous segment, if it doesn't already have one
const people = formatSegment(lastSegment, lastInitial);
peoples.push(people);
}
lastInitialOnly = initialOnly;
// Skip initial only segments
if (initialOnly) {
return;
}
}
lastInitial = null;
// Remove the initial from the words
// to avoid getting the initial calculated for the initial
segment = segment.filter(word => {
if (isInitial(word)) {
lastInitial = word;
return false;
}
return true;
});
lastSegment = segment;
});
// Process last segment
if (!lastInitialOnly) {
const people = formatSegment(lastSegment, lastInitial);
peoples.push(people);
}
});
return peoples;
}
process.addEventListener('click', _ => {
const peoples = doProcess();
const display = doDisplay(peoples);
output.value = display;
});
.row {
display: flex;
}
.row > * {
flex: 1 0;
}
<div class="row">
<h3>Input</h3>
<h3>Output</h3>
</div>
<div class="row">
<textarea id="input" rows="10">Guilcher, G.M., Harvey, M. & Hand, J.P.
Ri Liesner, Peter Tom Collins, Michael Richards
Manco-Johnson M, Santagostino E, Ljung R.
Jordan M, Michael Jackson & Willis B.</textarea>
<textarea id="output" rows="10"></textarea>
</div>
<button id="process" style="display: block;">Process</button>

add quotes to each item in a text file

I want to use this list of bad words for my input filtering. It's a plain list right now, but I need to convert it to JSON for my server to use.
I don't want to go through each line and add quotes and a ,. Is there a regex or fast way to add " ", to each line in a txt file?
Such that:
2g1c
2 girls 1 cup
acrotomophilia
alabama hot pocket
alaskan pipeline
Becomes
"2g1c",
"2 girls 1 cup",
"acrotomophilia",
"alabama hot pocket",
"alaskan pipeline",
...

Use backtick `
var txt=`2g1c
2 girls 1 cup
acrotomophilia
alabama hot pocket
alaskan pipeline`;
var arrayUntrimmed = txt.split("\n");
var array=arrayUntrimmed.map(function(a){return a.trim()});
(Note: This ECMAScript 6 feature supported from Firefox 34 and Chrome 41)

All you have to do is split the string at the new lines and drop the last item in the array (since it's empty).
var txt = '2g1c\n2 girls 1 cup\nacrotomophilia\nalabama hot pocket\nalaskan pipeline\n';
var array = txt.split('\n').slice(0, -1);
console.log(array)
You can then use Array.prototype.some as a predicate method to find out if a given string contains one or more of the blacklisted words.
var txt = '2g1c\n2 girls 1 cup\nacrotomophilia\nalabama hot pocket\nalaskan pipeline\n';
var array = txt.split('\n').slice(0, -1);
var input1 = 'not bad';
var input2 = 'An alaskan pipeline is quite creative...';
var input1HasBadWords = array.some(function (word) {
return input1.indexOf(word) > -1;
});
var input2HasBadWords = array.some(function (word) {
return input2.indexOf(word) > -1;
});
console.log('input1 is: ' + input1HasBadWords);
console.log('input2 is: ' + input2HasBadWords);
Your controller would look something like so:
const fs = require('fs');
app.post('/route', (req, res) => {
fs.readFile('/etc/hosts', 'utf8', (err, data) => {
if (err) {
res.sendStatus(500);
}
const badWords = data.split('\n').slice(0, -1);
const hasBadWords = badWords.some((word) => {
return req.body.input.indexOf(word) > -1;
});
if(hasBadWords) {
res.send('Dirty mouth? Clean it with orbit!');
} else {
res.send('You are very polite');
}
});
});

http://pastebin.com/U5phzWUM
I guess the easiest way is to use a software for this. It took me 30 sec to do this with SublimeText
http://www.sublimetext.com/docs/selection

You can use readline module. read and add quotes in each line.
readline: https://nodejs.org/api/readline.html