Historical errata for Rails for .NET Developers

In the example on page 23 , the generate script is demonstrated.

In the figure, the command text gets wrapped to the next line and the part of the command that gets wrapped has a blue typeface that does not match the red, bold typeface that the first part of the command had.

On PDF page 35 under section 2.3, the following ruby code is sampled:

puts “\\t#{5*10}”

and the result in the book is said to be

500

when the true result is (clearly)

50

On PDF page 39 on line 1 of the .NET code example a string of characters is present that is not .NET code:

#

The wording in the last paragraph of the to_s vs. ToString() section on page 34 implies that the an example of to_s was shown to the reader.

On page 36 the line puts flight.sub(/(w+)\\bto/, ‘PDX to’) doesn’t produce the listed output.

The first line of output in the flight example is actually the first line of code – flight = “United Airlines, Flight #312, ORD to LAX, 9:45AM to 11:45AM”

There are also some code color issues with the output of the flight example.

“A static method called Models() returns a list of available models that can be used.” Models is a property.

“In the body of the initializer, we have defined two instance variables, model and altitude.” There are 3 instance variables defined.

There’s 2 methods nested inside of a method for the C# 2.0 example.

Small issue with the LINQ version – if you want to keep the examples functionally equivalent then AddDays(–8) is incorrect.

The text/symbol “>” appears twice in the example of the generate script:

c:\\dev\\flight> ruby script\\generate model flight

c:\\dev\\flight> ruby script\\generate controller flights

The text/symbol “>” appears twice on this page in the example of the scaffold generate:

c:\\dev\\> rails flight

c:\\dev\\flight\\> ruby script\\generate scaffold flight

Missing a space in passengersArray - should read "passengers Array"

After adding the new column with rake db:migrate, the text says to add the new field to the existing view pages. It says to “Open app/views/new.html.erb” which doesn’t exist. It should say “Open app/views/books/new.html.erb”

It seems like the code example should include the changes that are being talked about in the text. Adding the code for the new field:

Purchased on

<%= f.date_select :purchased_on %>

Unexplained #END HIGHLIGHT comment. I’m guessing the arrows are supposed to stop at that line because the code after #END HIGHLIGHT didn’t change.

#BEGIN HIGHLIGHT comment. Guessing that the code is supposed to be highlighted with arrows.

The proposed show action potentially hits the database twice. Not a big deal if you’re consistently using the named route, but I’d probably use the ternary operator to determine whether or not we have a name parameter.

Few things on this page:

“header and footer to our views” - there isn’t really a footer being added. There’s a header and you’re styling the content.

It’s also unclear if the flights_enhanced layout’s header’s id is set correctly. If it is set correctly I think you should add styling for this element in scaffold.css. This would make your intentions clearer (the reader would have a visual confirmation).

There’s a lot of issues with the downloadable code in this section. Layouts render as html in my browser and a lot of it contains markup (<# START_HIGHLIGHT>, <# END_HIGHLIGHT>, etc).

The sentence on PDF p29 “Using the same technique, you should also go ahead and enhance app/views/NEW.html.erb in the same way.” should presumably reference app/view/EDIT.html/erb instead.

The ruby command is two lines but is not highlighted on the second line. This was very misleading, and caused me to have to go back and painfully correct my mistake.

The source listing for new.html.erb does not include the purchased_on field.

The comment about to_s appears before the code it refers to; perhaps it should be moved?

5 x 10 should be printed out as 50, not 500 as shown in the code listing.

The standard class for working with regular expressions in .NET is Regex, not RegExp.

The second output listing on the page should not include the first line. It is a repeat of the variable assignment, and wouldn’t be displayed.

The second output listing should not have the output colored green, as if each line contained a comment.

The List<> type is a collection, not an array. Either the text needs to be updated to note the distinction, or an actual array should be used in the C# code examples.

The command prompts have the > character escaped in the code listing but shouldn’t.

Shouldn’t the text “/flights-for-today/” map to the AirlinesController, not the FlightsController?

Shouldn’t the airports variable be prefixed with the @ symbol, since it’s a member of the generated view?

Either the id of the h1 element or the CSS needs to change, since they don’t have the same value (flights vs header) in the code listings.

puts flight.sub(/(w+)\\bto/, ‘PDX to’) # is a pattern match and should use the gsub method NOT the sub method

puts flight.sub(/(w)\\bto/, ’PDX to’) # the regular expression is incorrect; maybe: gsub(/\\w \\bto/, ‘PDX to’)

Context:
————————
Using a third-party gem from within your Rails code is dirt simple. Rails
knows to activate the RubyGems environment when it starts up, so all
you have to do is tell Rails which Rails your application depends upon.
You’ll then need to decide whether you want to bundle a copy of each

Description:
——————
the second line (bottom to top) of the las paragraph should say: “so all
you have to do is tell Rails which Gem” instead of “so all
you have to do is tell Rails which Rails”

“A symbol is globally unique, named representation of” should be “A symbol is a globally unique, named representation of”

Missing from code listing:

<%= will_paginate @passengers %>

But available in referenced download

“This additional line of code with result in a standard error message displayed inline,” should read “This additional line of code will result in a standard error message displayed inline,”

In the second paragraph of 3.1 Working with Collections and Iterators you state “…we may way want to synthesize an entirely new data set containing only those elements that meet certain criteria.” The word “way” shouldn’t be there.