<p>before(expr) succeeds if the expr sub-expression would match at the current position in the sequence, but expr is not included in the match. For instance, before("foo") succeeds if we are before a "foo". Look-ahead assertions can be negated with the bit-compliment operator.</p>
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<p>before(expr) succeeds if the expr sub-expression would match at the current position in the sequence, but expr is not included in the match. For instance, before("foo") succeeds if we are before a "foo". Look-ahead assertions can be negated with the bit-compliment operator.</p>
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