あとで書く

README.md

使い方

1. http://doc.ruby-lang.org/ja/1.9.3/class/Array.html の冒頭に追加

  <script src="http://cdnjs.cloudflare.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
  <script src="pre-to-mruby.js"></script>
  <script src="http://qiezi.me/projects/mruby-web-irb/mruby.js"></script>

2. pre をクリック
3. Eval をクリック

pre-to-mruby.js

(function () {
  var lines = [], printed = false, mrb, load_string_func;

  window.Module = {};
  window.Module['print'] = function (x) {
    lines.push(x);
    printed = true;
  };

  jQuery.fn.autogrow = function(options) {
    var settings = $.extend({
        extraLineHeight: 15,
        timeoutBuffer: 100
      }, options)
    var self = this;
    var timerId = self.removeData('timerId');
    if (timerId)
      clearTimeout(timerId);
    var handler = function() {
      self.each(function (i,e) {
        var scrollHeight = e.scrollHeight;
        var clientHeight = e.clientHeight;
        if (clientHeight < scrollHeight) {
          $(e).height(scrollHeight + settings.extraLineHeight);
        }
      });
      self.removeData('timerId');
    };
    self.data('timerId', setTimeout(handler, settings.timeoutBuffer))
  }
  $(document).on('keyup.autogrow', 'textarea', function() { $(this).autogrow(); });

  $(document).ready(function() {
    mrb = Module['_driver_open']();
    load_string_func = Module.cwrap("driver_execute_string",
                                    "number",
                                    ["number", "string"]);

    $("pre").on("click.replace", function() {
      var $this = $(this);
      $this.off("click.replace");
      var form = $("<form>");
      var btn = $("<button>Eval</button>");
      var textarea = $("<textarea style='width:100%'></textarea>").html($this.html());
      var output = $("<pre style='background:snow;display:none'></pre>");
      form.append(btn).append("<br>").append(textarea).append("<br>").append(output);
      textarea.autogrow();
      btn.on("click", function(e) {
        lines = [];
        printed = false;
        load_string_func(mrb, textarea.val());
        if (!printed) {
          window.Module['print']('<small><i>(no output)</i></small>');
        }
        output.html(lines.join("<br>")).show();
        return false;
      });
      $this.html(form);
    });

    window.onbeforeunload = function () {
      Module['_driver_close'](mrb);
    }
  });
}());