|
public static Func ( int args ) : |
||
| args | int | |
| return | ||
static CodeMemberMethod XF(int args)
{
var t = new CodeTypeReference("System.Linq.Expressions.Expression", Types.Func(args));
var m = CreateMethod("XF", t, "expr", args, true);
m.Comments.AddDocs(
XmlDocs.TypeParams(m.TypeParameters, t),
XmlDocs.Param("expr", "The " + XmlDocs.See(t) + " to return."),
XmlDocs.Summary("Creates a " + XmlDocs.See(t) + " expression tree."),
XmlDocs.Returns("Returns <paramref name=\"expr\" />.")
);
return(m);
}
static CodeMemberMethod F(int args)
{
var t = Types.Func(args);
var m = CreateMethod("F", t, "lambda", args, true);
m.Comments.AddDocs(
XmlDocs.TypeParams(m.TypeParameters, t),
XmlDocs.Param("lambda", "The " + XmlDocs.See(t) + " to return."),
XmlDocs.Summary("Creates a " + XmlDocs.See(t) + " delegate."),
XmlDocs.Returns("Returns <paramref name=\"lambda\" />.")
);
return(m);
}
static CodeMemberMethod RecFunc(int args)
{
var t = Types.Func(args);
var m = new CodeMemberMethod()
{
Attributes = MemberAttributes.Static | MemberAttributes.Public,
Name = "RecFunc",
ReturnType = t,
};
m.TypeParameters.AddRange(Types.GetTypeParameters(args, true).ToArray());
var a = "lambda";
m.Parameters.Add(new CodeParameterDeclarationExpression(new CodeTypeReference("Func", t, t), a));
m.Statements.ThrowWhenArgumentIsNull(a);
var expr = AppendArgs(new StringBuilder(), args);
expr.Append(" => lambda (RecFunc (lambda))");
AppendArgs(expr, args);
m.Statements.Add(new CodeMethodReturnStatement(new CodeSnippetExpression(expr.ToString())));
m.Comments.AddRange("From: http://blogs.msdn.com/madst/archive/2007/05/11/recursive-lambda-expressions.aspx");
m.Comments.AddDocs(
XmlDocs.TypeParams(m.TypeParameters, t),
XmlDocs.Param("lambda", "The " + XmlDocs.See(t) + " to use."),
XmlDocs.Summary("Creates a " + XmlDocs.See(t) + " delegate, which may be recursive."),
XmlDocs.Returns("Returns a " + XmlDocs.See(t) + " which (eventually) invokes <paramref name=\"lambda\"/>."),
XmlDocs.ArgumentNullException("lambda"),
XmlDocs.Remarks(
"<para>",
" The following example makes use of a recursive lambda:",
"</para>",
"<code lang=\"C#\">",
" Func<int, int> factorial = Lambda.RecFunc<int, int> (".Replace("<", "<"),
" fac => x => x == 0 ? 1 : x * fac (x-1));",
" Console.WriteLine (factorial (5)); // prints \"120\"",
"</code>"
)
);
return(m);
}
