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I thought the following two were equivalent:
named_scope :admin, lambda { |company_id| {:conditions => ['company_id = ?', company_id]} } named_scope :admin, lambda do |company_id| {:conditions => ['company_id = ?', company_id]} end but Ruby is complaining:
ArgumentError: tried to create Proc object without a block Any ideas?
682
A Proc object is an encapsulation of a block of code, which can be stored in a local variable, passed to a method or another Proc, and can be called. Proc is an essential concept in Ruby and a core of its functional programming features.
Procs are objects, blocks are notA proc (notice the lowercase p) is an instance of the Proc class. This lets us call methods on it and assign it to variables. Procs can also return themselves. In contrast, a block is just part of the syntax of a method call.
When using parameters prefixed with ampersands, passing a block to a method results in a proc in the method's context. Procs behave like blocks, but they can be stored in a variable. Lambdas are procs that behave like methods, meaning they enforce arity and return as methods instead of in their parent scope.
There are only two main differences. First, a lambda checks the number of arguments passed to it, while a proc does not. This means that a lambda will throw an error if you pass it the wrong number of arguments, whereas a proc will ignore unexpected arguments and assign nil to any that are missing.
it's a parser problem. try this
named_scope :admin, (lambda do |company_id| {:conditions => ['company_id = ?', company_id]} end) If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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