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NoMethodError: You have a nil object when you didn’t expect it! in Rails

NoMethodError: You have a nil object when you didn’t expect it! ?


While coding with Ruby on Rails you might have came across NoMethodError: You have a nil object when you didn't expect it!. Basically it is very common error for which solution is also very simple. NoMethodError: You have a nil object when you didn't expect it! means your code tried some operation with the object holding nil value.

NoMethodError: You have a nil object when you didn't expect it!

Sample Code which can reproduce this error:

Suppose, you initiate a variable called ‘a’ with an Empty Hash.

a = {}

Then you try to create a key :key and value as string ‘value’ in the hash a, like

a[:key] = ‘value’

Above steps will create a hash and will insert 1 key value pair in it properly.

But suppose after step 1, somehow your hash gets nil value in between by some code.

a = nil

And then you try to create key :key in the variable a

a[:key] = ‘value’

Then it will throw the exception NoMethodError: You have a nil object when you didn't expect it!

As variable ‘a’ is holding nil value, it won’t be able to create a key in it.

Whenever you get such kind of error in your codebase then just ensure that variables are properly initialized with intended data type and actually they are holding some value. By ensuring this you won’t be getting such kind of errors/exceptions.

Thus whenever you get NoMethodError: You have a nil object when you didn't expect it! just check what value the variable is holding and is that properly initialized and then your problem will be resolved.

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