C# (CSharp) Lucene.Net.QueryParsers.Surround.Parser Namespace

Note that this does not do line-number counting, but instead keeps track of the character position of the token in the input, as required by Lucene's Lucene.Net.Analysis.Token API.

This parser generates queries that make use of position information (Span queries). It provides positional operators (w and n) that accept a numeric distance, as well as boolean operators (and, or, and not, wildcards (/// and ?), quoting (with "), and boosting (via ^).

The operators (W, N, AND, OR, NOT) can be expressed lower-cased or upper-cased, and the non-unary operators (everything but NOT) support both infix (a AND b AND c) and prefix AND(a, b, c) notation.

The W and N operators express a positional relationship among their operands. N is ordered, and W is unordered. The distance is 1 by default, meaning the operands are adjacent, or may be provided as a prefix from 2-99. So, for example, 3W(a, b) means that terms a and b must appear within three positions of each other, or in other words, up to two terms may appear between a and b.