/// <summary>
/// Creates a new symbol reference pointing to a global var
/// </summary>
/// <param name="name">The name.</param>
/// <param name="envSymbol">The _ENV symbol.</param>
/// <returns></returns>
public static SymbolRef Global(string name, SymbolRef envSymbol)
{
return(new SymbolRef()
{
i_Index = -1, i_Type = SymbolRefType.Global, i_Env = envSymbol, i_Name = name
});
}
/// <summary>
/// Tries to get the reference of a symbol in the current execution state
/// </summary>
public DynValue EvaluateSymbol(SymbolRef symref)
{
if (symref == null)
{
return(DynValue.Nil);
}
return(m_Processor.GetGenericSymbol(symref));
}
/// <summary>
/// Reads a symbolref from a binary stream
/// </summary>
internal static SymbolRef ReadBinary(BinaryReader br)
{
SymbolRef that = new SymbolRef();
that.i_Type = (SymbolRefType)br.ReadByte();
that.i_Index = br.ReadInt32();
that.i_Name = br.ReadString();
return(that);
}
internal void ReadBinaryEnv(BinaryReader br, SymbolRef[] symbolRefs)
{
int idx = br.ReadInt32();
if (idx >= 0)
{
i_Env = symbolRefs[idx];
}
}
/// <summary>
/// Creates a closure from a bytecode address.
/// </summary>
/// <param name="address">The address.</param>
/// <param name="envTable">The env table to create a 0-upvalue</param>
/// <returns></returns>
private DynValue MakeClosure(int address, Table envTable = null)
{
this.CheckScriptOwnership(envTable);
Closure c;
if (envTable == null)
{
Instruction meta = m_MainProcessor.FindMeta(ref address);
// if we find the meta for a new chunk, we use the value in the meta for the _ENV upvalue
if ((meta != null) && (meta.NumVal2 == (int)OpCodeMetadataType.ChunkEntrypoint))
{
c = new Closure(this, address,
new SymbolRef[] { SymbolRef.Upvalue(WellKnownSymbols.ENV, 0) },
new DynValue[] { meta.Value });
}
else
{
c = new Closure(this, address, new SymbolRef[0], new DynValue[0]);
}
}
else
{
var syms = new SymbolRef[] {
new SymbolRef()
{
i_Env = null, i_Index = 0, i_Name = WellKnownSymbols.ENV, i_Type = SymbolRefType.DefaultEnv
},
};
var vals = new DynValue[] {
DynValue.NewTable(envTable)
};
c = new Closure(this, address, syms, vals);
}
return(DynValue.NewClosure(c));
}
