From wikipedia, I have a string like the following: Here are [[a variable number of words]] in brackets.

I think I'm being dense, as I can't think of a one-liner I can use to substitute the double square brackets with their contents, while at the same time replacing spaces with underscores within the brackets. In other words, I want to get Here are a_variable_number_of_words in brackets.

In reply to substitute characters in the RHS of a search & replace by Anonymous Monk

Title:
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