public Continuation Perform(Continuation c)
{
var expansion = c.Result;
c = c.PopResult();
return(c.Evaluate(env, expansion));
}
public override Continuation Evaluate(Continuation c, Datum args)
{
var argArray = args.ToArray();
var expression = argArray[0];
var environment = (LexicalEnvironment)argArray[1].CastObject();
return(c.Evaluate(environment, expression));
}
public override Continuation Evaluate(Continuation c, Datum args)
{
foreach (var ab in argBodies)
{
var closureEnv = ab.binding(env, args);
if (closureEnv == null)
{
continue;
}
return(c.Evaluate(closureEnv, ab.body));
}
throw bindError(args);
}
public override Continuation Evaluate(Continuation c, Environment env, Datum args)
{
var argList = args.ToArray();
if (argList.Length != 2)
{
throw c.error("Expected 2 arguments: (set! <symbol> <expression>). Got {0} instead", argList.Length);
}
var name = argList[0].CastIdentifier();
var expression = argList[1];
c = c.PushTask(new SetName(env, name));
return(c.Evaluate(env, expression));
}
public override Continuation Evaluate(Continuation c, Datum args)
{
foreach (var ab in argBodies)
{
var frameBindings = ab.binding(args);
if (frameBindings == null)
{
continue;
}
var closureEnv = env.NewFrame(frameBindings);
return(c.Evaluate(closureEnv, ab.body));
}
throw bindError(args);
}
public override Continuation Evaluate(Continuation c, LexicalEnvironment env, Datum args)
{
var argList = args.ToArray();
if (argList.Length != 2)
{
throw c.error("Expected 2 arguments: (define <symbol> <expression>). Got {0} instead", argList.Length);
}
var name = argList[0].CastSymbol();
var expression = argList[1];
c = c.PushTask(
tc => { env.Define(name, tc.Result);
return(tc); },
"define '{0}'", name);
return(c.Evaluate(env, expression));
}
public override Continuation Evaluate(Continuation c, LexicalEnvironment env, Datum args)
{
var argList = args.ToArray();
if (argList.Length < 1)
{
throw c.error("Expected at least 1 expression for begin. Got none.");
}
// Scope any local definitions.
var localEnv = env.NewFrame();
var remaining = argList.Reverse().ToArray();
for (var i = 0; i < remaining.Length; ++i)
{
if (i > 0)
{
c = c.PushTask(popResult, "Discard result");
}
c = c.Evaluate(localEnv, remaining[i]);
}
return(c);
}
public override Continuation Evaluate(Continuation c, Environment env, Datum args)
{
var argList = args.ToArray();
if (argList.Length < 1)
{
throw c.error("Expected at least 1 expression for begin. Got none.");
}
// Scope any local definitions.
var localEnv = new Environment(env);
var remaining = argList.Reverse().ToArray();
for (var i = 0; i < remaining.Length; ++i)
{
if (i > 0)
{
c = c.PushTask(Ignore.Instance);
}
c = c.Evaluate(localEnv, remaining[i]);
}
return(c);
}
