google docs script: printWordsBetweenAngleBrackets()

function printWordsBetweenAngleBrackets(){
  let doc = DocumentApp.getActiveDocument();
  let body = doc.getBody();
  let text = body.editAsText();
  
  // all the documents text as a long string AFAIK
  let textString = text.getText();
  
  let startToken = false;
  let tokens = [];
  let token = "";
  for (let i=0; i<textString.length;i++){
    let c = textString[i];
    
    if (c == "<"){
      //Logger.log(i, "<");
      startToken = true;
      continue;
    }
    
    if (c == ">"){
      tokens.push(token);
      token = "";
      startToken = false;
      continue;
    }
      
    if (startToken){
      token += c;
    }
  }
  
  tokens = new Set(tokens);
  tokens = Array.from(tokens)
  //Logger.log(tokens);

  tokens = tokens.sort();
  Logger.log(tokens);

  //Append a paragraph and a page break to the document body section directly.
  //body.appendParagraph("A paragraph.");
  //body.appendPageBreak();
}