esther-medina-quintero-parser-nearley/src/build-ast.js

Lab for language processors

/**
 * The ASTs of the Egg Lang 
 * @external Grammar
 * @see {@link https://ull-esit-pl-2122.github.io/temas/syntax-analysis/ast.html#gramatica-informal-de-los-arboles-del-parser-de-egg}
 */

/**
 * A function that builds a number value
 * @param {Token} token The token to be built
 * @return {Object} The number value
 */
function buildNumberValue([token]) {
  // console.log(token)
  return {
    type: "value",
    value: token.value,
    raw: token.text,
  };
}

/**
 * A function that builds a string value
 * @param {Token} token The token to be built
 * @return {Object} The string value
 */
function buildStringValue([token]) {
  return {
    type: "value",
    value: token.value.replace(/^"|"$/g, ""),
    raw: token.text,
  };
}

function buildArrayValue([token]) {

}


/**
 * A function that builds a word applies
 * @param {Array} word The word to be built
 * @param {Array} applies The applies to be built
 * @return {Object} The word applies
 */
function buildWordApplies([word, applies]) {
  if (applies == null) {
    word.type = "word";
    word.name = word.value;
    delete(word.value);
    delete(word.text);
    delete(word.toString);
    return word;
  }

  let ast = {
    type: "apply",
    operator: word,
    args: applies[0],
  }

  if (applies.length == 1) {
    return ast;
  }

  for (let i = 1; i < applies.length; i++) {
    let oldAst = ast;
    ast = {
      type: "apply",
      operator: oldAst,
      args: applies[i],
    };
  }
  return ast;
}

/**
 * A function that builds nested applies
 * @param {Array} parentExp The parent expression to be built
 * @param {Array} applies The applies to be built
 * @return {Array} The nested applies
 */
function buildNestedApplies([parentExp, applies]) {
  // console.log(parentExp);
  // console.log(applies);
  if (applies) return [parentExp].concat(applies);
  return [parentExp];
}

function buildArrayApplies([_, applies]) {
  return applies;
}

module.exports = { 
  buildNumberValue, 
  buildStringValue, 
  buildWordApplies, 
  buildArrayValue,
  buildNestedApplies
};