public DekiScriptExpression Visit(DekiScriptAccess expr, DekiScriptExpressionEvaluationState state)
{
DekiScriptExpression prefix = expr.Prefix.VisitWith(this, state);
DekiScriptExpression index = expr.Index.VisitWith(this, state);
DekiScriptAccess access = (DekiScriptAccess)DekiScriptExpression.Access(expr.Location, prefix, index);
if ((prefix is DekiScriptLiteral) && (index is DekiScriptLiteral))
{
DekiScriptLiteral result = DekiScriptExpressionEvaluation.Instance.Evaluate(access, state, false);
// check if result is a property
if (DekiScriptRuntime.IsProperty(result))
{
// retrieve property information
var descriptor = state.Runtime.ResolveRegisteredFunctionUri(((DekiScriptUri)result).Value);
if ((descriptor != null) && descriptor.IsIdempotent)
{
// evaluate property, since it never changes
return(state.Runtime.EvaluateProperty(expr.Location, result, state.Env));
}
return(DekiScriptExpression.Call(expr.Location, result, new DekiScriptList()));
}
return(result);
}
return(access);
}
public DekiScriptExpression Visit(DekiScriptAccess expr, DekiScriptOptimizerState state)
{
DekiScriptExpression prefix = expr.Prefix.VisitWith(this, state);
DekiScriptExpression index = expr.Index.VisitWith(this, state);
DekiScriptAccess access = new DekiScriptAccess(expr.Line, expr.Column, prefix, index);
if ((prefix is DekiScriptLiteral) && (index is DekiScriptLiteral))
{
// BUGBUGBUG (steveb): don't eval properties!
DekiScriptLiteral result = DekiScriptExpressionEvaluation.Instance.Evaluate(access, state.Env, false);
// check if result is a property
if (DekiScriptRuntime.IsProperty(result))
{
// retrieve property information
DekiScriptFunction function;
if (DekiScriptLibrary.Functions.TryGetValue(((DekiScriptUri)result).Value, out function))
{
if (function is DekiScriptFunctionNative)
{
DekiScriptFunctionNative native = (DekiScriptFunctionNative)function;
// check if function is idempotent; if so, execute it
if (native.IsIdempotent)
{
// evaluate property, since it never changes
return(DekiScriptRuntime.EvaluateProperty(result, state.Env));
}
}
}
return(new DekiScriptCall(expr.Line, expr.Column, result, new DekiScriptList(), false));
}
return(result);
}
return(access);
}
internal DekiScriptLiteral Evaluate(DekiScriptAccess expr, DekiScriptExpressionEvaluationState state, bool evaluateProperties)
{
DekiScriptLiteral prefix = state.Pop(expr.Prefix.VisitWith(this, state));
DekiScriptLiteral index = state.Pop(expr.Index.VisitWith(this, state));
switch (prefix.ScriptType)
{
case DekiScriptType.MAP: {
DekiScriptLiteral result = ((DekiScriptMap)prefix)[index];
if (evaluateProperties)
{
result = state.Runtime.EvaluateProperty(expr.Location, result, state.Env);
}
return(result);
}
case DekiScriptType.LIST: {
DekiScriptLiteral value = DekiScriptExpression.Constant(index.AsNumber());
DekiScriptLiteral result = ((DekiScriptList)prefix)[value];
if (evaluateProperties)
{
result = state.Runtime.EvaluateProperty(expr.Location, result, state.Env);
}
return(result);
}
case DekiScriptType.URI: {
DekiScriptUri uri = (DekiScriptUri)prefix;
// coerce the index type to STR
index = DekiScriptExpression.Constant(index.AsString());
if (index.ScriptType != DekiScriptType.STR)
{
throw new DekiScriptBadTypeException(expr.Location, index.ScriptType, new[] { DekiScriptType.STR });
}
// curry the argument
DekiScriptList args;
if (!uri.Arguments.IsNil)
{
// the uri already has curried parameters, make sure they are in LIST format; otherwise fail
if (uri.Arguments.ScriptType != DekiScriptType.LIST)
{
throw new DekiScriptBadTypeException(expr.Location, uri.Arguments.ScriptType, new[] { DekiScriptType.NIL, DekiScriptType.LIST });
}
args = new DekiScriptList((DekiScriptList)uri.Arguments);
}
else
{
args = new DekiScriptList();
}
args.Add(index);
return(new DekiScriptUri(uri.Value, args));
}
case DekiScriptType.STR: {
DekiScriptString text = (DekiScriptString)prefix;
// coerce the index type to NUM
double?value = index.AsNumber();
if (value == null)
{
throw new DekiScriptBadTypeException(expr.Location, index.ScriptType, new[] { DekiScriptType.NUM });
}
// retrieve character at given index position
int position = (int)value;
if ((position < 0) || (position >= text.Value.Length))
{
// index is out of bounds, return nil
return(DekiScriptNil.Value);
}
return(DekiScriptExpression.Constant(text.Value[position].ToString()));
}
case DekiScriptType.XML: {
string path = index.AsString();
if (path == null)
{
throw new DekiScriptBadTypeException(expr.Location, index.ScriptType, new[] { DekiScriptType.STR });
}
XDoc doc = ((DekiScriptXml)prefix).Value[path];
if (doc.HasName("html"))
{
doc = DekiScriptLibrary.CleanseHtmlDocument(doc);
}
return(new DekiScriptXml(doc));
}
case DekiScriptType.NIL:
return(DekiScriptNil.Value);
}
throw new DekiScriptBadTypeException(expr.Location, prefix.ScriptType, new[] { DekiScriptType.MAP, DekiScriptType.LIST, DekiScriptType.XML, DekiScriptType.STR, DekiScriptType.URI });
}
public DekiScriptOutputBuffer.Range Visit(DekiScriptAccess expr, DekiScriptExpressionEvaluationState state)
{
return(state.Push(Evaluate(expr, state, true)));
}
public DekiScriptLiteral Visit(DekiScriptAccess expr, DekiScriptEnv env)
{
return(Evaluate(expr, env, true));
}