public static Object BackQuoteReader(params Object[] args)
{
TextReader textReader = (TextReader)args[0];
ReadTable readTable = (ReadTable)args[1];
return(new Cons(Symbol.FromName("backquote"), new Cons(Read(textReader, readTable, null), null)));
}
public static object ReadString(string expression, Environment environment)
{
ReadTable readTable = (ReadTable)environment.GetValue(Symbol.FromName("*readtable*"));
object input = Reader.Read(new StringReader(expression), readTable);
return(input);
}
/// <summary>
/// Starts the toploop running using specified input, output and error streams
///
/// </summary>
/// <param name="reader"></param>
/// <param name="writer"></param>
/// <param name="error"></param>
public void Run(TextReader reader, TextWriter writer, TextWriter error)
{
Symbol LAST = Symbol.FromName("?");
while (true)
{
try
{
Object o = trace ? Runtime.EvalString("(eval (prl (read (in Console))))", environment)
: Runtime.EvalString("(eval (read (in Console)))", environment);
if (o == Reader.EOFVALUE)
{
return;
}
if (tracereturn)
{
writer.Write(prompt);
writer.WriteLine(Printer.WriteToString(o));
}
environment.AssignLocal(LAST, o);
}
catch (LSharpException e)
{
error.WriteLine(e.Message);
}
catch (Exception e)
{
error.WriteLine(e.GetBaseException());
}
}
}
public static Object ReadString(Cons args, Environment environment)
{
ReadTable readTable = (ReadTable)environment.GetValue(Symbol.FromName("*readtable*"));
TextReader textReader = new StringReader((string)args.First());
return(Reader.Read(textReader, readTable));
}
public static Object AtomReader(int c, TextReader textReader)
{
if (((Char)c) == ')')
{
return(Symbol.FromName(")"));
}
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append((char)c);
bool done = false;
do
{
int nextChar = textReader.Peek();
if ((nextChar == -1) || (TerminatingCharP((Char)nextChar)))
{
done = true;
}
else
{
c = textReader.Read();
stringBuilder.Append((char)c);
}
} while (!done);
string token = stringBuilder.ToString();
Double d;
try
{
// Try reading the number as an integer
if (Double.TryParse(token, System.Globalization.NumberStyles.Integer, NumberFormatInfo.InvariantInfo, out d))
{
return((int)d);
}
// Try reading the number as a double
if (Double.TryParse(token, System.Globalization.NumberStyles.Any, NumberFormatInfo.InvariantInfo, out d))
{
return(d);
}
else
{
return(Symbol.FromName(token));
}
}
catch (FormatException) // OH NO MONO!
{
System.Diagnostics.Trace.WriteLine("Why???? " + token);
return(Symbol.FromName(token));
}
}
public static Object AtomReader(int c, TextReader textReader)
{
if (((Char)c) == ')')
{
return(RPAREN);
}
if (((Char)c) == ']')
{
return(RBRACKET);
}
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append((char)c);
bool done = false;
do
{
int nextChar = textReader.Peek();
if ((nextChar == -1) || (IsTerminator((Char)nextChar)))
{
done = true;
}
else
{
c = textReader.Read();
stringBuilder.Append((char)c);
}
} while (!done);
string token = stringBuilder.ToString();
Double d;
// Try reading the number as an integer
if (Double.TryParse(token, System.Globalization.NumberStyles.Integer, NumberFormatInfo.InvariantInfo, out d))
{
return((int)d);
}
// Try reading the number as a double
if (Double.TryParse(token, System.Globalization.NumberStyles.Any, NumberFormatInfo.InvariantInfo, out d))
{
return(d);
}
else
{
return(Symbol.FromName(token));
}
}
public static Object UnQuoteReader(params Object[] args)
{
TextReader textReader = (TextReader)args[0];
ReadTable readTable = (ReadTable)args[1];
if (textReader.Peek() == '@')
{
textReader.Read();
return(new Cons(Symbol.FromName("splice"), new Cons(Read(textReader, readTable, null), null)));
}
return(new Cons(Symbol.FromName("unquote"), new Cons(Read(textReader, readTable, null), null)));
}
public static Object Read(Cons args, Environment environment)
{
ReadTable readTable = (ReadTable)environment.GetValue(Symbol.FromName("*readtable*"));
TextReader textReader = args.First() as TextReader;
object eofValue = Reader.EOFVALUE;
if (args.Length() > 1)
{
eofValue = args.Second();
}
return(Reader.Read(textReader, readTable, eofValue));
}
public void InitialiseLSharpBindings()
{
isresetting = true;
foreach (Extension e in extensions)
{
InitSymbols(e.type, e.delegatetype);
extmark++;
}
// leppie: should this not be Assign() ?
// read table
Assign(Symbol.FromName("*readtable*"), ReadTable.DefaultReadTable());
// Macros
foreach (Type t in macroextensions)
{
InitMacros(t);
}
isresetting = false;
}
/// <summary>
/// Creates a new environment which has access to a previous environment
/// </summary>
public Environment(Environment environment)
{
this.previousEnvironment = environment;
AssignLocal(Symbol.FromName("environment"), this);
}
public Environment()
{
AssignLocal(Symbol.FromName("environment"), this);
}
public static Expression Compile1(Object s, Environment environment)
{
// Literals are constants
if (Runtime.IsLiteral(s))
{
return(Expression.Constant(s));
}
// Special Syntax gets expanded and compiled
if (Runtime.IsSsyntax(s))
{
return(Compile1(Runtime.ExpandSSyntax(s), environment));
}
// Symbols are variable references
if (s is Symbol)
{
return(CompileVarRef((Symbol)s));
}
// Special Syntax gets expanded and compiled
if (Runtime.IsSsyntax(Runtime.Car(s)))
{
object expansion = Runtime.ExpandSSyntax(((Pair)s).First());
return(Compile1(new Pair(expansion, (Pair)s), environment));
}
if (s is Pair)
{
object f = ((Pair)s).First();
// Special Forms
if (f == Symbol.FromName("if"))
{
return(Compiler.CompileIf(((Pair)s).Rest(), environment));
}
if (f == Symbol.FromName("quote"))
{
return(Compiler.CompileQuote(((Pair)s).Rest(), environment));
}
if (f == Symbol.FromName("call-clr"))
{
return(Compiler.CompileCall((Pair)((Pair)s).Rest(), environment));
}
if (f == Symbol.FromName("call-instance"))
{
return(Compiler.CompileInstanceCall((Pair)((Pair)s).Rest(), environment));
}
if (f == Symbol.FromName("fn"))
{
return(Compiler.CompileFn((Pair)((Pair)s).Rest(), environment));
}
if (f == Symbol.FromName("macro"))
{
return(Compiler.CompileMac((Pair)((Pair)s).Rest(), environment));
}
if (f == Symbol.FromName("quasiquote"))
{
return(Compiler.CompileQuasiQuote((Pair)((Pair)s).Rest(), environment));
}
if ((f is Symbol) && (environment.Contains((Symbol)f)))
{
object value = environment.GetValue((Symbol)f);
// Macros get invoked at compile time, then their results are themeselves compiled
if (value is Macro)
{
object expansion = ((Macro)value).Call(Runtime.AsArray(((Pair)s).Rest()));
return(Compile1(expansion, environment));
}
}
// It must be a function call
return(CompileFunctionCall(f, ((Pair)s).Rest(), environment));
}
throw new LSharpException(string.Format("Bad object in expression: ", s), environment);
}
private static void ProcessKeyArguments(Cons argumentNameList, Cons argumentList,
Environment localEnvironment)
{
// Make sure that all of the defined key arguments are inserted to the local enviroment with their
// defaults.
while (argumentNameList != null)
{
Symbol argumentName = null;
object argumentValue = null;
// We need to get the name of the argument, it can either be just the name or, it can be
// it's own Cons with the name and an expression for the default value.
if (argumentNameList.Car() is Cons)
{
// It is a Cons, so extract the name and the default value. Because the default can be
// any expression, we need to evaluate the value every time the function is called.
argumentName = (Symbol)argumentNameList.Caar();
argumentValue = Runtime.Eval(argumentNameList.Cadar(), localEnvironment);
}
else
{
argumentName = (Symbol)argumentNameList.Car();
}
// Add this variable to the closure's environment, then advance to the next parameter.
localEnvironment.AssignLocal(argumentName, argumentValue);
argumentNameList = (Cons)argumentNameList.Cdr();
}
// Now that the parameters and their defaults have been added to the environment we can now
// process the supplied arguments.
while (argumentList != null)
{
// Because these are keyed parameters, the caller needs to specify the name of each
// parameter.
if (argumentList.Car().GetType() != typeof(Symbol))
{
throw new LSharpException("Key parameters must be specified by name.");
}
// Grab the current parameter and the value associated with it. Then make sure that this
// is a keyword.
Symbol keywordName = (Symbol)argumentList.Car();
object argumentValue = argumentList.Cadr();
if (keywordName.Name[0] != ':')
{
throw new LSharpException(keywordName + " is not a valid keyword.");
}
// Now that we know they supplied a keyword, create a symbol out of it and make sure that
// it exists.
//keywordName = new Symbol(keywordName.Name.Substring(1));
keywordName = Symbol.FromName(keywordName.Name.Substring(1));
if (localEnvironment.Contains(keywordName) == false)
{
throw new LSharpException(keywordName + " is not a recognised keyword.");
}
// Update the parameter with the value that the user specified and then move onto the next
// argument in the list.
localEnvironment.AssignLocal(keywordName, argumentValue);
argumentList = (Cons)argumentList.Cddr();
}
}
