incr-regex-package/lib/rxprint.js

An incremental regular expression parser in JavaScript; useful for input validation, RegExp

// module: rxprint.js
/** 
 * Copyright (c) 2016, Nurul Choudhury
 * 
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 * 
 */

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.printExpr = printExpr;
exports.printExprS = printExprS;
exports.printExprQ = printExprQ;
exports.printExprN = printExprN;

var _rxtree = require("./rxtree");

function printExpr(exp, paren) {
  if (paren && exp && exp.oper) return "(" + printExpr(exp) + ")";
  if (exp && exp.oper) {
    if (exp.oper.type == 'B') {
      if (exp.oper.op == '.') return "(" + printExpr(exp.left) + "." + printExpr(exp.right) + ")";
      return "(" + printExpr(exp.left) + "|" + printExpr(exp.right) + ")";
    } else if (exp.oper.type == 'U') {
      return "(" + printExpr(exp.left, false) + exp.oper.val + ")";
    }
  } else if (exp === _rxtree.DONE) return "<DONE>";else return exp.val;
}

function printExprS(exp, ctxPriority) {
  if (exp && exp.oper) {
    if (exp.oper.type == 'B') {
      if (exp.oper.op == '.') return ctxPriority > 2 ? "(" + printExprS(exp.left, 2) + printExprS(exp.right, 2) + ")" : printExprS(exp.left, 2) + printExprS(exp.right, 2);
      return ctxPriority > 1 ? "(" + printExprS(exp.left, 1) + "|" + printExprS(exp.right, 1) + ")" : printExprS(exp.left, ctxPriority + 1) + "|" + printExprS(exp.right, ctxPriority);
    } else if (exp.oper.type == 'U') {
      return ctxPriority > 3 ? "(" + printExprS(exp.left, 1) + ")" + exp.oper.val : printExprS(exp.left, 3) + exp.oper.val;
    }
  } else if (exp === _rxtree.DONE) return "<DONE>";else return exp.val || '~~~';
}

function printExprQ(exp, paren) {
  if (paren && exp && exp.oper) return "(" + printExprQ(exp) + ")";
  if (exp && exp.oper) {
    if (exp.oper.type == 'B') {
      if (exp.oper.op == '.') return "(" + printExprQ(exp.left) + "." + printExprQ(exp.right) + ")";
      return "(" + printExprQ(exp.left) + "|" + printExprQ(exp.right) + ")";
    } else if (exp.oper.type == 'U') {
      return "(" + printExprQ(exp.left, false) + exp.oper.val + ")";
    }
  } else if (exp === _rxtree.DONE) return "<DONE>";else return "'" + (exp.val || '~~~') + "'";
}

function printExprN(exp, paren) {
  if (paren && exp && exp.oper) return "(" + printExpr(exp) + ")";
  if (exp && exp.oper) {
    if (exp.oper.type == 'B') {
      if (exp.oper.op == '.') {
        if (exp.nextNode) return "(" + printExprN(exp.left) + "." + printExprN(exp.nextNode) + ")";else return printExprN(exp.left);
      }
      return "(" + printExprN(exp.left) + "|" + printExprN(exp.right) + ")";
    } else if (exp.oper.type == 'U') {
      if (exp.nextNode) {
        return "((" + printExpr(exp.left, false) + exp.oper.val + ")." + printExprN(exp.nextNode) + ")";
      }
      return "(" + printExpr(exp.left, false) + exp.oper.val + ")";
    }
  } else if (exp === _rxtree.DONE) return "<DONE>";else {
    if (exp && exp.nextNode) return "(" + (exp.val || '~~~') + "." + printExprN(exp.nextNode) + ")";
    return exp ? exp.val : '';
  }
}