Rails 4 strong params - using array in hash

Question

I have seen a lot of samples of Rails code, and I saw two versions of nested attributes in strong params:

params.require(:smth).permit(:a, b: [])
params.require(:smth).permit(:a, { b: [] })

Why do I need to use braces in the second example? Thanks in advance.

Those 2 examples are identical - the braces around a hash are optional when it is the last argument to a method — Frederick Cheung
– Frederick Cheung, Commented Sep 11, 2014 at 10:55

Roman Kiselenko · Accepted Answer · 2014-09-11 10:50:37Z

1

When you have several hash in permit params you should separate by braces:

params.require(:smth).permit(:a, { b: [] }, { c: [] })

this should raise syntax error:

params.require(:smth).permit(:a,  b: [] , c: [] )

answered Sep 11, 2014 at 10:50

Roman Kiselenko

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1 Comment

Thanks! It's pretty simple :)