andregrigon

How to Debug Chez Scheme Programs

R. Kent Dybvig

August 2002

1. Basic debugging techniques
   1. Kinds of failure
   2. Understanding error messages
   3. Staring at the code
2. Simplifying the code and input

zlw5009

Building a Foundation with &blocks

What is a Block?

Blocks... What are they anyway? You've probably used them without even realizing it and most certainly have seen them, but do you know what they are?

If we wanted to take a simplistic approach at defining a block we could say:

A block is a chunk of code contained within the do..end or { curly braces } syntax that is to be executed at some point in time.

With that being said, if you've ever used the Enumerable#map or Enumerable#each method, you've probably used a block. Lets take a look at two different types of blocks before we go into more detail about what a block really is.

letladi

var fs = require('fs');

function csvParser(filePath) {
	fs.readFile(filePath, 'utf8', function(err, data) {
		if (err) {
			throw err;
		} else {
			var result = [];
			var lines = data.split('\n');
			var headings = lines[0].split(',');

arunoda

# add the email package
meteor add email

mebezac

    <div id="main" role="main">
      <div class="container">
         <div class="row">
          <div class="span12" id="top-div"> <!--! added "top-div" id to help with ajax -->
            <%= render 'layouts/messages' %>
            <%= yield %>
          </div>
        </div>
        <footer>
        </footer>

Whoaa512

Meteor.startup(function() {
  Template.fb_pic.pic = function() {// helper function to display the pic on the page
    var userProfile;
    userProfile = Meteor.user().profile;

    if(userProfile) { // logic to handle logged out state
      return userProfile.picture;
    }
  };
});