Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

38 lines (29 sloc) 0.916 kb
require 'monadic'
class AgeTooLowError < ArgumentError; end
class AgeTooHighError < ArgumentError; end
valid_age = ->(age_expr) {
age = age_expr.to_i
case
when age <= 0; Failure(AgeTooLowError.new(age_expr))
when age > 130; Failure(AgeTooHighError.new(age_expr))
else Success(age)
end
}
valid_name = ->(name) {
case
when name =~ /\w{3,99}/i; Success(name)
else Failure('Invalid name')
end
}
params = {age: 32, name: 'Andrzej', postcode: '50000'}
Person = Struct.new(:name, :age)
result = Validation() do
check { valid_name.(params[:name]) }
check { valid_age.(params[:age]) }
end
case result
when Failure; puts "Something went wrong: #{result.fetch}"
when Success; person = Person.new(*result.fetch); puts "We have a person #{person.inspect}"
end
# Failure: Something went wrong: [#<AgeTooHighError: 200>]
# Success: We have a person #<struct Person name="Andrzej", age=32>
Jump to Line
Something went wrong with that request. Please try again.