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The method for carrying out negative Look-ahead when there is an indefinite number of closing brackets is to use a non-greedy quantifier. This ensures that the Look-ahead does not consume the closing bracket that matches with the opening bracket in the pattern. Here is an example for matching a string that contains "foo" but is not followed by any closing bracket:

foo(?!.*?\))

In this example, the non-greedy quantifier .*? matches any character zero or more times, but as few times as possible to satisfy the negative Look-ahead (?!.*?) which checks if there is no closing bracket ahead. This ensures that the matching stops before any closing bracket that matches with the opening bracket is consumed by the Look-ahead.