/// <summary> /// Enables defining in-line parser grammars using LINQ. /// </summary> /// <typeparam name="TParseResult">The type of the elements that are originally generated from parsing the source elements.</typeparam> /// <typeparam name="TSource">The type of the source elements; typically, this will be an anonymous compiler-generated type.</typeparam> /// <typeparam name="TResult">The type of the elements that are generated from parsing the source elements.</typeparam> /// <param name="source">The parser query context to be projected.</param> /// <param name="selector">A function that projects the current result of the query context.</param> /// <returns>A new query context that is the projection of the specified query context using the specified <paramref name="selector"/>.</returns> public static BinaryParserQueryContext <TParseResult, TResult> Select <TParseResult, TSource, TResult>( this BinaryParserQueryContext <TParseResult, TSource> source, Func <TSource, TResult> selector) { Contract.Requires(source != null); Contract.Requires(selector != null); Contract.Ensures(Contract.Result <BinaryParserQueryContext <TParseResult, TResult> >() != null); return(new BinaryParserQueryContext <TParseResult, TResult>( source.Parser, selector(source.Value))); }
public static IEnumerable <TResult> ParseBinary <TResult>( this IEnumerable <byte> source, Func <BinaryParserQueryContext <byte, IParser <byte, byte> >, BinaryParserQueryContext <byte, IParser <byte, IEnumerable <TResult> > > > grammarSelector) { Contract.Requires(source != null); Contract.Requires(grammarSelector != null); Contract.Ensures(Contract.Result <IEnumerable <TResult> >() != null); var parser = new InlineBinaryParser <IEnumerable <TResult> >(); var proxyParser = (IBinaryParser <byte>)parser; // The proxy allows the grammar author to use base methods such as Success and Failure // while still allowing type inference to work correctly; i.e., the Parse method is unavailable // and thus the type of the proxy is based solely on TSource, without requiring TResult to // be in an input position in grammarSelector. var context = new BinaryParserQueryContext <byte, IParser <byte, byte> >( proxyParser, parser.Next); var grammar = grammarSelector(context); Contract.Assume(grammar != null); IParser <byte, IEnumerable <TResult> > start = grammar.Value; Contract.Assume(start != null); // enableBranchOptimizations must be false: See the comments in the first Parse extension for details. using (var cursor = source.ToCursor(forwardOnly: true, enableBranchOptimizations: false)) { foreach (var result in parser.Parse(cursor, start).Concat()) { yield return(result); } } }