Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::xpressive::before — Look-ahead assertion.
template<typename Xpr> unspecified before(Xpr const & xpr);
before(xpr) succeeds if the xpr sub-expression would match at the current position in the sequence, but xpr 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.
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| Notes: | before(xpr) is equivalent to the perl (?=...) extension. ~before(xpr) is a negative look-ahead assertion, equivalent to the perl (?!...) extension. |
| Copyright © 2003, 2004 Eric Niebler |