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String "false" to_bool ... or how to convert Rails/SimpleForm radio buttons to boolean

This gist was writen in 2012 and it was solving specific problem in Rails & SimpleForm. Some fellow developers were pointing out this may be out dated concept. That's why I advise everyone to read comment section bellow to have a full grasp of alternative solutions

other sources that may be helpful to understand why this may not be best idea:

module StringToBoolean
def to_bool
return true if self == true || self =~ (/^(true|t|yes|y|1)$/i)
return false if self == false || self.blank? || self =~ (/^(false|f|no|n|0)$/i)
raise"invalid value for Boolean: \"#{self}\"")
class String; include StringToBoolean; end
module BooleanToBoolean
def to_bool;return self; end
class TrueClass; include BooleanToBoolean; end
class FalseClass; include BooleanToBoolean; end
# However there is also better practice to do it by using
ActiveRecord::ConnectionAdapters::Column.value_to_boolean( something )
2.0.0dev :019 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('1')
=> true
2.0.0dev :020 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('0')
=> false
2.0.0dev :021 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('true')
=> true
2.0.0dev :022 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('false')
=> false
2.0.0dev :023 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('nil')
=> false
2.0.0dev :024 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('t')
=> true
2.0.0dev :025 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean('cat')
=> false
2.0.0dev :026 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean(true)
=> true
2.0.0dev :027 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean(false)
2.0.0dev :035 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean(1)
=> true
2.0.0dev :036 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean(2)
=> false
2.0.0dev :037 > ActiveRecord::ConnectionAdapters::Column.value_to_boolean(0)
=> false
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@nickcampbell18 thankyou!!!


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Ruby Facets / to_b

require 'facets/boolean'

[ nil, '', 1, 0, '1', '0', true, false, 'true', 'false', 'yes', 'no' ].each do |value|
  puts "#{value.inspect}: #{value.to_b}"


nil: false
"": false
1: true
0: false
"1": true
"0": false
true: true
false: false
"true": true
"false": false
"yes": true
"no": false

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Thank you! @nickcampbell18 +100

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nrogap commented May 21, 2019

Thank you! @nickcampbell18 +2999

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Please close this gist man, It creates so many issues, i start to see this code into a lot of places, create pr to ruby if you think it's a right way to handle booleans. Thanks a lot!

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i start to see this code into a lot of places

and all are pointing to this gist as a single source ?

create pr to ruby

There is a good reason why this is not introduced in Ruby (or the notion of single boolean class which would TrueClass and FalseClass more info ) But this is not about Ruby it's about specifc usecase in Rails and SimpleForm. It was written in 2012 and it was solving an issue. I cannot tell if it's still valid as I didn't use Simple Form in 8 years but I see people having a conversation on this gist which I think is valuable.

if you think it's a right way to handle booleans

I don't, but this gist is not about Ruby

Please close this gist man

I will not as I see value in the comment section. But I welcome if you drop here a comment guiding others how to better approach issue originally described or your thoughts on boolean in Ruby. I'm pretty sure everyone would welcome a constructive comment with a solution

have a lovely day

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@equivalent if it's not about ruby, then replace:

class TrueClass; include BooleanToBoolean; end
class FalseClass; include BooleanToBoolean; end

and ask people to use your class without patch ruby. I think if it's not about ruby then use helper method or class, or what you want. If you show how to patch standart ruby class, then make ruby PR.

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