Ruby - TypeError: no implicit conversion of Hash into String
52,228
Solution 1
The error is a result of calling Array#to_sentence
on a hash.
More specifically, fruits
is a Hash
, and calling fruits.each { ... }
returns the original fruits
Hash
unchanged. Thus calling fruits.to_sentence
causes the observed error.
Here's a fixed-up version with comments denoting the changes:
require 'json'
text = "Hello world"
json = '{"fruits": [{"name": "Apple", "location": "Harbor"}, {"name": "Banana", "location": "Kitchen"}, {"name": "Mango", "location": "Bedroom"}]}'
fruits = JSON.parse(json)['fruits'] # append ['fruits']
def format_fruits(fruits)
fruits.map do |fruit| # change each -> map
"\n\n#{ fruit['name'] }, #{ fruit['location'] }" # delete puts, [0]
end.join # change to_sentence -> join
end
text += format_fruits(fruits)
puts text
Output:
Hello world
Apple, Harbor
Banana, Kitchen
Mango, Bedroom
Solution 2
In-case your json always contains "fruits" key, you can achieve this quite easily. Here:
fruits = JSON.parse(json)
#=> {"fruits"=>[{"name"=>"Apple", "location"=>"Harbor"}, {"name"=>"Banana", "location"=>"Kitchen"}, {"name"=>"Mango", "location"=>"Bedroom"}]}
fruits["fruits"].each { |hash|
puts "\n\n#{hash['name']}, #{hash['location']}"
}
Another way to do this without using fruits
key:
fruits.values.first.each { |hash|
puts "\n\n#{hash['name']}, #{hash['location']}"
}
Author by
Mark Boulder
Updated on January 10, 2022Comments
-
Mark Boulder over 2 years
Trying to parse some JSON, byt why is
text
empty?Desired output:
text
should returnHello world\n\nApple, Harbor\n\nBanana, Kitchen\n\nMango, Bedroom
text = "Hello world" json = '{"fruits": [{"name": "Apple", "location": "Harbor"}, {"name": "Banana", "location": "Kitchen"}, {"name": "Mango", "location": "Bedroom"}]}' fruits = JSON.parse(json) def format_fruits(fruits) fruits.each do |fruit| puts "\n\n#{ fruit[0]['name'] }, #{ fruit[0]['location'] }" end.to_sentence end text += format_fruits(fruits) text
Current output:
TypeError: no implicit conversion of Hash into String from (irb):5:in `+' from (irb):5 from /home/mark/.gem/ruby/2.1.1/gems/railties-4.1.7/lib/rails/commands/console.rb:90:in `start' from /home/mark/.gem/ruby/2.1.1/gems/railties-4.1.7/lib/rails/commands/console.rb:9:in `start' from /home/mark/.gem/ruby/2.1.1/gems/railties-4.1.7/lib/rails/commands/commands_tasks.rb:69:in `console' from /home/mark/.gem/ruby/2.1.1/gems/railties-4.1.7/lib/rails/commands/commands_tasks.rb:40:in `run_command!' from /home/mark/.gem/ruby/2.1.1/gems/railties-4.1.7/lib/rails/commands.rb:17:in `<top (required)>' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:247:in `require' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:247:in `block in require' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:232:in `load_dependency' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:247:in `require' from /home/mark/myapp/bin/rails:8:in `<top (required)>' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:241:in `load' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:241:in `block in load' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:232:in `load_dependency' from /home/mark/.gem/ruby/2.1.1/gems/activesupport-4.1.7/lib/active_support/dependencies.rb:241:in `load' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/commands/rails.rb:6:in `call' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/command_wrapper.rb:38:in `call' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application.rb:180:in `block in serve' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application.rb:153:in `fork' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application.rb:153:in `serve' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application.rb:128:in `block in run' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application.rb:122:in `loop' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application.rb:122:in `run' from /home/mark/.gem/ruby/2.1.1/gems/spring-1.1.3/lib/spring/application/boot.rb:18:in `<top (required)>' from /home/mark/.rubies/ruby-2.1.1/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require' from /home/mark/.rubies/ruby-2.1.1/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require' from -e:1:in `<main>'irb(main):006:0> text => "Hello world" irb(main):007:0>
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krex about 9 yearsIt would be nice to have an accompanying explanation as to what the issue actually was.