So, is it a bad idea to fetch data from "arguments"? (Rotten belches in 3, 2, 1...)

makeplain.js

function makeplain(strAccents)
{
    if(strAccents==undefined)
            return "";

    strAccents = strAccents.split('');
    var strAccentsOut = new Array();
    var strAccentsLen = strAccents.length;
    var accents = 'ÀÁÂÃÄÅàáâãäåÒÓÔÕÕÖØòóôõöøÈÉÊËèéêëðÇçÐÌÍÎÏìíîïÙÚÛÜùúûüÑñŠšŸÿýŽž';
    var accentsOut = ['A','A','A','A','A','A','a','a','a','a','a','a','O','O','O','O','O','O','O','o','o','o','o','o','o','E','E','E','E','e','e','e','e','e','C','c','D','I','I','I','I','i','i','i','i','U','U','U','U','u','u','u','u','N','n','S','s','Y','y','y','Z','z'];
    for (var y = 0; y < strAccentsLen; y++)
            {
            if (accents.indexOf(strAccents[y]) != -1)
                    {
                    strAccentsOut[y] = accentsOut[accents.indexOf(strAccents[y])];
                    }
                    else
                    strAccentsOut[y] = strAccents[y];
            }
    strAccentsOut = strAccentsOut.join('');

    return strAccentsOut.toLowerCase();
}

strf.js

function strf(){
  var args = arguments,
      arg_l = args.length - 1;
  var onReplace = function(arg, i){
    i = parseInt(i);
    if ( i >= 0 && i < arg_l )
      return args[i + 1];
    return arg;
  };
  return args[0].replace(/\$\{([0-9]+)\}/g, onReplace);
}

// strf('Hello ${0}', 'World'); // "Hello World"
// strf('Hello ${0}'); // "Hello ${0}"
// strf('${0}${1}', 'Hello ', 'World'); // "Hello World"

trimshim.js

// Trim shim for Internet Explorer.
// Author: Ben Rowe
// Source: http://stackoverflow.com/questions/2308134/trim-in-javascript-not-working-in-ie

if(typeof String.prototype.trim !== 'function') {
  String.prototype.trim = function() {
    return this.replace(/^\s+|\s+$/g, ''); 
  }
}