Ruby for Rails phần 8 pdf

... arity. Ruby offers several variations on the callable method-or-function theme. We’ll look next at another form of anonymous function: the lambda. B Part 4 Rails through Ruby, Ruby through Rails The ... you get more out of Rails by knowing more about Ruby. The goals here are the goals of the book itself: ■ Learning the Ruby foundations of specific Rails techniques ■ Using y...

Ngày tải lên: 06/08/2014, 09:20

... and exceptions 225 8. 4 Error handling and exceptions Way back in chapter 1, we looked at how to test code for syntax errors: $ ruby -cw filename.rb Passing the -cw test means Ruby can run your ... use an absolute path for a file. This may happen if you create a class or module with a name that’s similar to the name of a Ruby built-in class or module. For example, Ruby come...

Ngày tải lên: 06/08/2014, 09:20

... huge roles in Ruby and Rails. Some of the founda- tional Ruby libraries upon which Rails is built use hashes to pass data around; in particular, the Ruby CGI library makes your CGI form data available ... of the irb session format for the code examples, and you can often try the examples with small variations to get a feel for how Ruby behaves. 9.1 Ruby s literal constructors...

Ngày tải lên: 06/08/2014, 09:20

... application-related skills and tasks 85 Converting legacy data to ActiveRecord 85 The irb-based Rails application console 89 3.4 Summary 90 Ruby for Rails RUBY TECHNIQUES FOR RAILS DEVELOPERS DAVID A. BLACK MANNING Greenwich (74° ... BLACK MANNING Greenwich (74° w. long.) vii PART ITHE RUBY/ RAILS LANDSCAPE 1 1 ■ How Ruby works 3 2 ■ How Rails works 33 3 ■ Ruby...

Ngày tải lên: 06/08/2014, 09:20

... in Ruby and shipped with Ruby) , lightTPD CGI Library CGI data processing routines Parses incoming form data Part of the Ruby standard library ERb "Embedded Ruby& quot; Templating system for ... extension (require it) ruby -rprofile version Show Ruby version information ruby version A Rails application walk-through 45 Initializing the databases To create the database fo...

Ngày tải lên: 06/08/2014, 09:20

... CHAPTER 3 Ruby- informed Rails development because of Ruby (Ruby doesn’t care), but because leaving the parentheses off is a standard Rails convention. The common idioms you use in Rails aren’t ... afraid of get- ting some error messages). 84 CHAPTER 3 Ruby- informed Rails development Free-form programmatic model enhancement Let’s say you have a Rails application in which yo...

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... object 942912 Loading object 94 289 2 Loading object 94 288 2 The first suitcase off the plane is 94 288 2 The cargo hold example shows how you can use an existing module for a new class. Sometimes it ... your Ruby programs. Sure enough, Ruby gives you a full suite of programming techniques for creat- ing objects on a batch or factory basis. You don’t have to define a separate price...

Ngày tải lên: 06/08/2014, 09:20

... "b", "y"] Another common use case for split is performing a conversion from a flat, text- based configuration file to a Ruby data format—array, hash, or something fancier What are ... of Ruby built-in methods take regular expressions as arguments and perform selection or modification on one or more string objects. Regular expressions are used, for example, to sca...

Ngày tải lên: 06/08/2014, 09:20

... the model and its associated entities for a next level of information. This information, in turn, might be used for in-house reports, richer on-screen information displays, or sales profiling. ... cosmetic. The consistent “Rubyness” of a Rails application makes for a consistent development experience: It’s easier to think in Ruby the whole time than it is to switch back and forth. (...

Ngày tải lên: 06/08/2014, 09:20