diff options
Diffstat (limited to 'guides/source/autoloading_and_reloading_constants.md')
| -rw-r--r-- | guides/source/autoloading_and_reloading_constants.md | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/guides/source/autoloading_and_reloading_constants.md b/guides/source/autoloading_and_reloading_constants.md index c4fac1cff5..9e78eebf82 100644 --- a/guides/source/autoloading_and_reloading_constants.md +++ b/guides/source/autoloading_and_reloading_constants.md @@ -114,6 +114,16 @@ certain nesting does not necessarily correlate with the namespaces at the spot. Even more, they are totally independent, take for instance ```ruby +module X + module Y + end +end + +module A + module B + end +end + module X::Y module A::B # (3) @@ -141,9 +151,10 @@ executed, and popped after it. * A singleton class opened with `class << object` gets pushed, and popped later. -* When any of the `*_eval` family of methods is called using a string argument, +* When `instance_eval` is called using a string argument, the singleton class of the receiver is pushed to the nesting of the eval'ed -code. +code. When `class_eval` or `module_eval` is called using a string argument, +the receiver is pushed to the nesting of the eval'ed code. * The nesting at the top-level of code interpreted by `Kernel#load` is empty unless the `load` call receives a true value as second argument, in which case @@ -290,7 +301,9 @@ order. The ancestors of those elements are ignored. 2. If not found, then the algorithm walks up the ancestor chain of the cref. -3. If not found, `const_missing` is invoked on the cref. The default +3. If not found and the cref is a module, the constant is looked up in `Object`. + +4. If not found, `const_missing` is invoked on the cref. The default implementation of `const_missing` raises `NameError`, but it can be overridden. Rails autoloading **does not emulate this algorithm**, but its starting point is @@ -313,7 +326,7 @@ relative: `::Billing::Invoice`. That would force `Billing` to be looked up only as a top-level constant. `Invoice` on the other hand is qualified by `Billing` and we are going to see -its resolution next. Let's call *parent* to that qualifying class or module +its resolution next. Let's define *parent* to be that qualifying class or module object, that is, `Billing` in the example above. The algorithm for qualified constants goes like this: @@ -450,8 +463,9 @@ Also, this collection is configurable via `config.autoload_paths`. For example, by adding this to `config/application.rb`: ```ruby -config.autoload_paths += "#{Rails.root}/lib" +config.autoload_paths << "#{Rails.root}/lib" ``` +`config.autoload_paths` is accessible from environment-specific configuration files, but any changes made to it outside `config/application.rb` don't have an effect. The value of `autoload_paths` can be inspected. In a just generated application it is (edited): |