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copy edit AS guide [ci skip]

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Vijay Dev 2012-06-02 21:46:39 +05:30
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12
guides/source/active_support_core_extensions.textile
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@ -156,7 +156,7 @@ NOTE: Defined in +active_support/core_ext/object/duplicable.rb+.
h4. +deep_dup+
The +deep_dup+ method returns deep copy of a given object. Normally, when you +dup+ an object that contains other objects, ruby does not +dup+ them. If you have array with a string, for example, it will look like this:
The +deep_dup+ method returns deep copy of a given object. Normally, when you +dup+ an object that contains other objects, ruby does not +dup+ them. If you have an array with a string, for example, it will look like this:
<ruby>
array = ['string']
@ -189,7 +189,7 @@ array #=> ['string']
duplicate #=> ['foo']
</ruby>
If object is not duplicable +deep_dup+ will just return this object:
If object is not duplicable, +deep_dup+ will just return this object:
<ruby>
number = 1
@ -201,12 +201,10 @@ NOTE: Defined in +active_support/core_ext/object/deep_dup.rb+.
h4. +try+
There are a lot of situations where you want to call a method on the receiver object if the object is not +nil+, so your code remains safe from unhandled +NoMethodError+ exceptions. The simplest way to achieve this is with conditional statements, which add unnecessary clutter. The alternative is to
use +try+.
+try+ is like +Object#send+ except that it returns +nil+ if sent to +nil+.
When you want to call a method on an object only if it is not +nil+, the simplest way to achieve it is with conditional statements, adding unnecessary clutter. The alternative is to use +try+. +try+ is like +Object#send+ except that it returns +nil+ if sent to +nil+.
Here is an example:
<ruby>
# without try
unless @number.nil?
@ -217,7 +215,7 @@ end
@number.try(:next)
</ruby>
Another example is this code from +ActiveRecord::ConnectionAdapters::AbstractAdapter+ +@logger+ could be +nil+, but you don't check it and write in an optimistic style:
Another example is this code from +ActiveRecord::ConnectionAdapters::AbstractAdapter+ where +@logger+ could be +nil+. You can see that the code uses +try+ and avoids an unnecessary check.
<ruby>
def log_info(sql, name, ms)