Mark specific words with asterisks (Javascript)-CodePudding

I have an array of objects with a set of certain words like entities. For example :

footnotes: [
  { sourceText: 'red'},
  { sourceText: 'green'},
  { sourceText: 'yellow'},
  { sourceText: 'purple'},
  { sourceText: 'gray'},
  { sourceText: 'blue'}
]

And I have some random sentences. For example: 'I drive a red car among green fields and look at the gray sky'

The goal is to mark words with asterisks according to the object of entities:

'I drive a red* car among green** fields and look at the gray*** sky'

I'm trying to do this in a loop with silce and Regexp but I can't concatenate the string correctly

How can this be done ?

Here is my code

footnotes = [{
    sourceText: "red",
    solve: false
  },
  {
    sourceText: "green",
    solve: false
  },
  {
    sourceText: 'yellow',
    solve: false
  },
  {
    sourceText: "purple",
    solve: false
  },
  {
    sourceText: "grey",
    solve: false
  },
  {
    sourceText: "blue",
    solve: false
  }
]

starGenerate = function(count) {
  let result = ''
  
  for (let i = 0; i < count; i  ) {
    result  = '*'
  }
  
  return result
},


let post = {
  id: 21321,
  data: {},
  lead: 'I drive a red car among green fields and look at the gray sky'
}


post.check = function() {
  let str, concat = ''
  let self = this;
  let starcounter = 0

  for (let i = 0; i < self.entities.length; i  ) {
    let reg = new RegExp(`${self.entities[i].sourceText}`);

    if (match = reg.exec(self.lead) && self.entities[i].solve === false) {
      concat = self.lead.replace(reg, `${self.entities[i].sourceText   starGenerate(  starcounter)}`)
      self.entities[i].solve = true
    }
  }
}

post.entities = footnotes

CodePudding user response：

You can do this with one regular expression (using |), and then use the callback argument of replace to insert the asterisks. Your function starGenerate is not really needed, as there is the repeat method.

function putAsterisks(footnotes, sentence) {
    let alternatives = footnotes.map(({sourceText}) => sourceText).join("|");
    let regex = RegExp("\\b("   alternatives   ")\\b", "gi");
    let starCount = 1;
    return sentence.replace(regex, m => m   "*".repeat(starCount  ));
}

// Example:
let footnotes = [{ sourceText: 'red'}, { sourceText: 'green'}, { sourceText: 'yellow'}, { sourceText: 'purple'}, { sourceText: 'gray'}, { sourceText: 'blue'}];
let sentence = 'I drive a red car among green fields and look at the gray sky';

console.log(putAsterisks(footnotes, sentence));

This assumes that the source texts do not contain characters that have a special meaning in regular expressions. If this could happen, then use this answer to first escape those words.

CodePudding user response：

You can do the same without regex by splitting your string and using map among all the words. This works fine as long as there is no further punctuation in your input string

const footnotes=[{sourceText:"red",solve:!1},{sourceText:"green",solve:!1},{sourceText:"yellow",solve:!1},{sourceText:"purple",solve:!1},{sourceText:"grey",solve:!1},{sourceText:"blue",solve:!1}];

const input = 'I drive a red car among green fields and look at the grey sky'
const footnotesIndex = footnotes.reduce( (acc,i) => (acc[i.sourceText] = i.solve,acc),{});
let star=1
const result = input.split(" ").map( word =>footnotesIndex[word] != undefined ? word   "*".repeat(star  ) : word).join(" ");
console.log(result);