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export function findIndentation(input) {  let pos = 0;  const stack = [0];  const topOfStack = () => stack[stack.length - 1];
  const result = {};
  const regex = /( *).*(?:$|\r?\n|\r)/g;  let match;  while ((match = regex.exec(input)) != null) {    const [line, indent] = match;
    // The last match will always have length 0. In every other case, some    // characters will be matched (possibly only the end of line chars).    if (line.length === 0) break;
    const indentSize = indent.length;    const prevSize = topOfStack();
    const indentPos = pos + indentSize;
    if (indentSize > prevSize) {      // Indent -- always only 1.      stack.push(indentSize);      result[indentPos] = 1;    } else if (indentSize < prevSize) {      // Dedent -- can be multiple levels.      const prevLength = stack.length;      while (topOfStack() !== indentSize) {        stack.pop();      }      result[indentPos] = -1 * (prevLength - stack.length);    }    pos += line.length;  }  // Ensure that there is a matching DEDENT for every remaining INDENT.  if (stack.length > 1) {    result[pos] = 1 - stack.length;  }  return result;}