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/Ruby on Rails 6.0

class ActionController::ParameterMissing

Parent:
KeyError

Raised when a required parameter is missing.

params = ActionController::Parameters.new(a: {})
params.fetch(:b)
# => ActionController::ParameterMissing: param is missing or the value is empty: b
params.require(:a)
# => ActionController::ParameterMissing: param is missing or the value is empty: a

© 2004–2019 David Heinemeier Hansson
Licensed under the MIT License.