JS: best way to keep track of unique key/value pairings?-CodePudding

I am iterating through objects of font data and want to push or add their postscript name and style as a key/value pair. The postscript name will always be the regular version of the postscript so I need to keep track of the style with it. For example, I want my data structure to look like:

[
   { "Arial-MT", "Bold" },
   { "Arial-MT", "Regular"}
]

While iterating though, if I come across another postscript_name that is Arial-MT and style of either Bold or Regular, I don't want to add it to my data object. What is the cleanest approach to this?

CodePudding user response：

Use an object containing Sets of strings.

const styles = {
    "Ariel-MT": new Set(["Bold", "Regular"])
};

postscript_data.forEach(([postscript_name, postscript_style]) => {
    if (styles[postscript_name]) {
        styles[postscript_name].add(postscript_style);
    } else {
        style[postscript_name] = new Set([postscript_style])
    }
});

CodePudding user response：

I've correct the data structure you provide as an array of objects:

const data = [
   { "Arial-MT": "Bold" },
   { "Arial-MT": "Regular"},
   { "Arial-MT": "Bold" },
   { "Arial-MT": "Regular"},
];
let visited = [];
let result = [];
for(const obj of data){
  const [k,v] = Object.entries(obj)[0];
  if(!visited.includes(`${k}_${v}`)){
      const new_obj = {}
      new_obj[k] = v;
      result.push(new_obj);
    visited.push(`${k}_${v}`);
  }
}
console.log(result)