| // sprintf() for JavaScript 0.7-beta1 |
| // http://www.diveintojavascript.com/projects/javascript-sprintf |
| // |
| // Copyright (c) Alexandru Marasteanu <alexaholic [at) gmail (dot] com> |
| // All rights reserved. |
| var strRepeat = require('./helper/strRepeat'); |
| var toString = Object.prototype.toString; |
| var sprintf = (function() { |
| function get_type(variable) { |
| return toString.call(variable).slice(8, -1).toLowerCase(); |
| } |
| |
| var str_repeat = strRepeat; |
| |
| var str_format = function() { |
| if (!str_format.cache.hasOwnProperty(arguments[0])) { |
| str_format.cache[arguments[0]] = str_format.parse(arguments[0]); |
| } |
| return str_format.format.call(null, str_format.cache[arguments[0]], arguments); |
| }; |
| |
| str_format.format = function(parse_tree, argv) { |
| var cursor = 1, tree_length = parse_tree.length, node_type = '', arg, output = [], i, k, match, pad, pad_character, pad_length; |
| for (i = 0; i < tree_length; i++) { |
| node_type = get_type(parse_tree[i]); |
| if (node_type === 'string') { |
| output.push(parse_tree[i]); |
| } |
| else if (node_type === 'array') { |
| match = parse_tree[i]; // convenience purposes only |
| if (match[2]) { // keyword argument |
| arg = argv[cursor]; |
| for (k = 0; k < match[2].length; k++) { |
| if (!arg.hasOwnProperty(match[2][k])) { |
| throw new Error(sprintf('[_.sprintf] property "%s" does not exist', match[2][k])); |
| } |
| arg = arg[match[2][k]]; |
| } |
| } else if (match[1]) { // positional argument (explicit) |
| arg = argv[match[1]]; |
| } |
| else { // positional argument (implicit) |
| arg = argv[cursor++]; |
| } |
| |
| if (/[^s]/.test(match[8]) && (get_type(arg) != 'number')) { |
| throw new Error(sprintf('[_.sprintf] expecting number but found %s', get_type(arg))); |
| } |
| switch (match[8]) { |
| case 'b': arg = arg.toString(2); break; |
| case 'c': arg = String.fromCharCode(arg); break; |
| case 'd': arg = parseInt(arg, 10); break; |
| case 'e': arg = match[7] ? arg.toExponential(match[7]) : arg.toExponential(); break; |
| case 'f': arg = match[7] ? parseFloat(arg).toFixed(match[7]) : parseFloat(arg); break; |
| case 'o': arg = arg.toString(8); break; |
| case 's': arg = ((arg = String(arg)) && match[7] ? arg.substring(0, match[7]) : arg); break; |
| case 'u': arg = Math.abs(arg); break; |
| case 'x': arg = arg.toString(16); break; |
| case 'X': arg = arg.toString(16).toUpperCase(); break; |
| } |
| arg = (/[def]/.test(match[8]) && match[3] && arg >= 0 ? '+'+ arg : arg); |
| pad_character = match[4] ? match[4] == '0' ? '0' : match[4].charAt(1) : ' '; |
| pad_length = match[6] - String(arg).length; |
| pad = match[6] ? str_repeat(pad_character, pad_length) : ''; |
| output.push(match[5] ? arg + pad : pad + arg); |
| } |
| } |
| return output.join(''); |
| }; |
| |
| str_format.cache = {}; |
| |
| str_format.parse = function(fmt) { |
| var _fmt = fmt, match = [], parse_tree = [], arg_names = 0; |
| while (_fmt) { |
| if ((match = /^[^\x25]+/.exec(_fmt)) !== null) { |
| parse_tree.push(match[0]); |
| } |
| else if ((match = /^\x25{2}/.exec(_fmt)) !== null) { |
| parse_tree.push('%'); |
| } |
| else if ((match = /^\x25(?:([1-9]\d*)\$|\(([^\)]+)\))?(\+)?(0|'[^$])?(-)?(\d+)?(?:\.(\d+))?([b-fosuxX])/.exec(_fmt)) !== null) { |
| if (match[2]) { |
| arg_names |= 1; |
| var field_list = [], replacement_field = match[2], field_match = []; |
| if ((field_match = /^([a-z_][a-z_\d]*)/i.exec(replacement_field)) !== null) { |
| field_list.push(field_match[1]); |
| while ((replacement_field = replacement_field.substring(field_match[0].length)) !== '') { |
| if ((field_match = /^\.([a-z_][a-z_\d]*)/i.exec(replacement_field)) !== null) { |
| field_list.push(field_match[1]); |
| } |
| else if ((field_match = /^\[(\d+)\]/.exec(replacement_field)) !== null) { |
| field_list.push(field_match[1]); |
| } |
| else { |
| throw new Error('[_.sprintf] huh?'); |
| } |
| } |
| } |
| else { |
| throw new Error('[_.sprintf] huh?'); |
| } |
| match[2] = field_list; |
| } |
| else { |
| arg_names |= 2; |
| } |
| if (arg_names === 3) { |
| throw new Error('[_.sprintf] mixing positional and named placeholders is not (yet) supported'); |
| } |
| parse_tree.push(match); |
| } |
| else { |
| throw new Error('[_.sprintf] huh?'); |
| } |
| _fmt = _fmt.substring(match[0].length); |
| } |
| return parse_tree; |
| }; |
| |
| return str_format; |
| })(); |
| |
| module.exports = sprintf; |