ruby - Rails 4 model formatting and hashes (really basic) -

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i have basic validation in model:

  validates :student_number, :presence => true,                     :length => { :maximum => 255 },                     :uniqueness => true

so that? here's best guess, if kindly tell me i'm mistaken, i'd appreciate it.

validates method. send symbol :first_name, :presence => true, is...a hash :presence key , true value?

except doesn't hash, @ least not according docs.

and :length => { :maximum => 255 } same sort of entity (hash?) :presence => true expects hash argument?

thanks assistance.

ruby allows drop parentheses , brackets if can infer locations itself; in case, rewrite code as:

validates(:student_number, { :presence => true,                              :length => { :maximum => 255 },                              :uniqueness => true })

which method call, passing first argument attribute validate, , second argument validation options, hash.

note: explanation bit of simplification, validates bit more complicated in how handles arguments. see here more details on how works exactly.


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