diff options
Diffstat (limited to 'railties/guides')
| -rw-r--r-- | railties/guides/source/active_support_core_extensions.textile | 83 | ||||
| -rw-r--r-- | railties/guides/source/caching_with_rails.textile | 6 |
2 files changed, 84 insertions, 5 deletions
diff --git a/railties/guides/source/active_support_core_extensions.textile b/railties/guides/source/active_support_core_extensions.textile index c04e49281e..0941953d1c 100644 --- a/railties/guides/source/active_support_core_extensions.textile +++ b/railties/guides/source/active_support_core_extensions.textile @@ -725,6 +725,64 @@ WARNING: This method returns precise results in Ruby 1.9. In older versions of R NOTE: Defined in +active_support/core_ext/module/introspection.rb+. +h5. Qualified Constant Names + +The standard methods +const_defined?+, +const_get+ , and +const_set+ accept +bare constant names. Active Support extends this API to be able to pass +relative qualified constant reference expressions. + +The new methods are +qualified_const_defined?+, +qualified_const_get+, and ++qualified_const_set+. Their arguments are assumed to be qualified constant +names relative to their receiver: + +<ruby> +Object.qualified_const_defined?("Math::PI") # => true +Object.qualified_const_get("Math::PI") # => 3.141592653589793 +Object.qualified_const_set("Math::Phi", 1.618034) # => 1.618034 +</ruby> + +Arguments may be bare constant names: + +<ruby> +Math.qualified_const_get("E") # => 2.718281828459045 +</ruby> + +These methods are analogous to their builtin counterparts. In particular, ++qualified_constant_defined?+ accepts an optional second argument in 1.9 +to be able to say whether you want the predicate to look in the ancestors. +This flag is taken into account for each constant in the expression while +walking down the path. + +For example, given + +<ruby> +module M + X = 1 +end + +module N + class C + include M + end +end +</ruby> + ++qualified_const_defined?+ behaves this way: + +<ruby> +N.qualified_const_defined?("C::X", false) # => false (1.9 only) +N.qualified_const_defined?("C::X", true) # => true (1.9 only) +N.qualified_const_defined?("C::X") # => false in 1.8, true in 1.9 +</ruby> + +As the last example implies, in 1.9 the second argument defaults to true, +as in +const_defined?+. + +For coherence with the builtin methods only relative paths are accepted. +Absolute qualified constant names like +::Math::PI+ raise +NameError+. + +NOTE: Defined in +active_support/core_ext/module/qualified_const.rb+. + h4. Synchronization The +synchronize+ macro declares a method to be synchronized: @@ -1620,6 +1678,31 @@ end NOTE: Defined in +active_support/core_ext/string/inflections.rb+. +h5. +deconstantize+ + +Given a string with a qualified constant reference expression, +deconstantize+ removes the rightmost segment, generally leaving the name of the constant's container: + +<ruby> +"Product".deconstantize # => "" +"Backoffice::UsersController".deconstantize # => "Backoffice" +"Admin::Hotel::ReservationUtils".deconstantize # => "Admin::Hotel" +</ruby> + +Active Support for example uses this method in +Module#qualified_const_set+: + +<ruby> +def qualified_const_set(path, value) + QualifiedConstUtils.raise_if_absolute(path) + + const_name = path.demodulize + mod_name = path.deconstantize + mod = mod_name.empty? ? self : qualified_const_get(mod_name) + mod.const_set(const_name, value) +end +</ruby> + +NOTE: Defined in +active_support/core_ext/string/inflections.rb+. + h5. +parameterize+ The method +parameterize+ normalizes its receiver in a way that can be used in pretty URLs. diff --git a/railties/guides/source/caching_with_rails.textile b/railties/guides/source/caching_with_rails.textile index 721c791a33..4273d0dd64 100644 --- a/railties/guides/source/caching_with_rails.textile +++ b/railties/guides/source/caching_with_rails.textile @@ -289,11 +289,7 @@ ActionController::Base.cache_store = :file_store, "/path/to/cache/directory" With this cache store, multiple server processes on the same host can share a cache. Servers processes running on different hosts could share a cache by using a shared file system, but that set up would not be ideal and is not recommended. The cache store is appropriate for low to medium traffic sites that are served off one or two hosts. -Note that the cache will grow until the disk is full unless you periodically clear out old entries. You can call +ActiveSupport::Cache::FileStore#cleanup+ to remove entries older than a specified time. - -<ruby> -Rails.cache.cleanup(:not_accessed_in => 2.days) -</ruby> +Note that the cache will grow until the disk is full unless you periodically clear out old entries. h4. ActiveSupport::Cache::MemCacheStore |