Object#try

Object#try is an ActiveSupport extension that calls a method on an object only if the object responds to it. If the object does not respond to the method, it returns nil instead of raising a NoMethodError. This is particularly useful when working with objects that may or may not have certain methods, or when chaining method calls on objects that could be nil.

Signature

Parameter	Type	Description
method_name	Symbol or String	The name of the method to call
*args	Array	Arguments to pass to the method
&block	Block	A block to pass to the method

Code Examples

# Basic usage - call method if it exists
user = User.new(name: "John")
user.try(:name)           # => "John"
user.try(:email)          # => nil (method does not exist)

# With arguments
user.try(:format_name, :uppercase)

# With a block
user.try(:names) { |n| n.upcase }

# Safe navigation alternative
# Instead of: @user && @user.profile && @user.profile.name
@user.try(:profile).try(:name)

Common Use Cases

1. Handling potentially nil objects: Avoid explicit nil checks when calling methods on objects that might be nil.

2. Working with dynamic attributes: Call methods that may or may not exist based on the object class or configuration.

3. Chained method calls: Safely navigate through nested associations where intermediate objects might be nil.

Edge Cases and Gotchas

• Calling try on nil always returns nil — this is the main feature, not a bug.

• Private methods: By default, try does not call private methods. Use try! or pass the method as a string to access private methods in some cases.

• NoMethodError vs nil: If you want an error to be raised when the method does not exist, use try! instead.

• Performance: try uses respond_to? internally, so there is a slight overhead compared to direct method calls.

Return Value

Returns the result of the method call if the object responds to the method, otherwise returns nil.

See Also

• Object#tap — useful when you want to keep chaining while inspecting an object
• Object#present? — returns the object if it is present, nil otherwise
• Object#dig — safely extract nested values from hashes and arrays