ruby - How can I improve the code to delete items in an array in the following case? -

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i have code:

array = ['notice', 'warning', 'error']  array.delete('notice')  if flash[:notice] array.delete('warning') if flash[:warning] array.delete('error')   if flash[:error]

since there repeated names, in order shorten code, use interpolation perform part of code:

array.delete('notice')  if flash[:notice] array.delete('warning') if flash[:warning] array.delete('error')   if flash[:error]

how can in 1 step?

i tryed this

array.each { |item|   array.delete("#{item}") if flash[:"#{item}"] }

but doesn't work good.

that happens because you're modifying array on iterate.
should work

array.clone.each { |item|   array.delete("#{item}") if flash[:"#{item}"] }

try running , without clone on sample input

array = ['notice', 'warning', 'error'] flash = {:warning => 1, :error => 2}  ...  p array

but there's no need invoke delete manually, can user reject:

array = array.reject! { |item| flash[:"#{item}"] }

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