private bool ParseFactorExpression(TokenReader reader, out Expression result)
{
Token tok = reader.Peek();
if (tok.Is(Keyword.LeftParen))
{
reader.Read();
if (!this.ParseExpression(reader, out result))
{
return false;
}
if (!this.Expect(reader, Keyword.RightParen))
{
return false;
}
return true;
}
if (tok.Is(Keyword.Not))
{
return this.ParseNotExpression(reader, out result);
}
if (tok.Is(Keyword.Minus))
{
return this.ParseNegativeExpression(reader, out result);
}
if (tok.Is(Keyword.New))
{
return this.ParseNewExpression(reader, out result);
}
if (tok.Is(Keyword.Nil))
{
reader.Read();
result = new LiteralExpression(tok, null);
return true;
}
if (tok.Is(Keyword.True))
{
reader.Read();
result = new LiteralExpression(tok, true);
return true;
}
if (tok.Is(Keyword.False))
{
reader.Read();
result = new LiteralExpression(tok, false);
return true;
}
LiteralToken literalTok = tok as LiteralToken;
if (literalTok != null)
{
result = new LiteralExpression(tok, literalTok.Value);
reader.Read();
return true;
}
if (tok.Is(Keyword.Address))
{
return this.ParseAddressExpression(reader, out result);
}
if (tok is IdentifierToken || tok.Is(Keyword.Inherited))
{
ReferenceExpression refExpr = null;
if (!this.ParseReferenceExpression(reader, out refExpr))
{
result = null;
return false;
}
result = refExpr;
return true;
}
string message = string.Format(
System.Globalization.CultureInfo.CurrentCulture,
Properties.Resources.Parser_Unexpected,
tok != null ? tok.ToString() : Properties.Resources.Parser_EndOfFile);
this.log.Write(new Message(reader.Path, reader.Line, reader.Column, Severity.Error, message));
result = null;
return false;
}
private bool TryEmitLiteralExpression(
LiteralExpression expression,
CompilerContext context,
Scope scope,
MethodImpl method,
out TypeDefinition valueType)
{
if (expression.Value == null)
{
method.Statements.Add(new AsmStatement { Instruction = "xor eax,eax" });
return context.TryFindTypeByName("^", out valueType);
}
if (expression.Value is int)
{
if ((int)expression.Value == 0)
{
method.Statements.Add(new AsmStatement { Instruction = "xor eax,eax" });
}
else
{
method.Statements.Add(new AsmStatement { Instruction = string.Format("mov eax,{0}", expression.Value) });
}
return context.TryFindTypeByName("integer", out valueType);
}
if (expression.Value is char)
{
method.Statements.Add(new AsmStatement { Instruction = string.Format("mov eax,{0}", (int)expression.Value) });
return context.TryFindTypeByName("character", out valueType);
}
if (expression.Value is string)
{
string label = method.Module.DefineLiteralString((string)expression.Value);
method.Statements.Add(new AsmStatement { Instruction = string.Format("lea eax,[offset {0}]", label) });
return context.TryFindTypeByName("#0character", out valueType);
}
if (expression.Value is decimal)
{
decimal exprValue = (decimal)expression.Value;
if (exprValue == 0.0M)
{
method.Statements.Add(new AsmStatement { Instruction = "fldz" });
}
else if (exprValue == 1.0M)
{
method.Statements.Add(new AsmStatement { Instruction = "fld1" });
}
else
{
string label = method.Module.DefineConstant((double)exprValue);
method.Statements.Add(new AsmStatement { Instruction = string.Format("fld qword ptr [{0}]", label) });
}
return context.TryFindTypeByName("double", out valueType);
}
if (expression.Value is bool)
{
bool boolVal = (bool)expression.Value;
if (boolVal)
{
method.Statements.Add(new AsmStatement { Instruction = "mov eax,1" });
}
else
{
method.Statements.Add(new AsmStatement { Instruction = "xor eax,eax" });
}
return context.TryFindTypeByName("boolean", out valueType);
}
valueType = null;
return false;
}