private static FunctionElement CreateMain()
{
var symbols = LanguageSymbols.Instance;
LanguageFunction functionInfo = new LanguageFunction();
functionInfo.Name = "!_Main";
functionInfo.Arguments = new List <LanguageFunction.FunctionArg>();
functionInfo.ReturnTypes = new List <LanguageType>();
symbols.AddUserFunction(functionInfo);
FunctionElement funcElement = new FunctionElement();
funcElement.Info = functionInfo;
StatementListElement statements = new StatementListElement();
funcElement.AddChild(statements);
FunctionCallElement callElement = new FunctionCallElement();
LanguageFunction mainFuncInfo = null;
try
{
mainFuncInfo = symbols.GetFunction("Main", new List <string>());
}
catch (CompilationException)
{
Compilation.WriteError("Main() wasn't found. Did you forget it?", -1);
}
callElement.FunctionInfo = mainFuncInfo;
callElement.CallArguments = new List <ValueElement>();
statements.AddChild(callElement);
SingleGenOpElement exitElement = new SingleGenOpElement();
exitElement.Operation = new GenOp {
Code = GenCodes.Exit, ArgCount = 0
};
statements.AddChild(exitElement);
return(funcElement);
}
/// <summary>
/// Build expression value. It's called from ParseExpression
/// </summary>
/// <param name="lexemes">List of lexemes</param>
/// <param name="pos">Position of current parsed lexeme</param>
/// <param name="flags">Control flags. ExpressionFlags.None to ignore all flags</param>
/// <param name="elem">Builded value element. null if it's not a value</param>
/// <returns>Position of a next lexeme</returns>
private int ParseExpressionValue(List <Lexeme> lexemes, int pos, ExpressionFlags flags, out ValueElement elem)
{
MultipleValElement multipleVals = new MultipleValElement();
if (lexemes[pos].Source == "(")
{
List <ValueElement> values;
pos = ExtractSeparatedExpressions(lexemes, pos, flags | ExpressionFlags.ForbidMultiple, out values);
if (pos >= (lexemes.Count - 1))
{
Compilation.WriteError("Unexpected end of file. Did you forget ')' and ';' ?", -1);
}
foreach (var i in values)
{
multipleVals.AddValue(i);
}
} //"("
else if (lexemes[pos].Code == Lexeme.CodeType.Number)
{
var val = new ConstValElement
{
Type = m_symbols.GetTypeOfConstVal(lexemes[pos].Source),
Value = lexemes[pos].Source
};
++pos;
elem = val;
return(pos);
}
else if (m_currentFunction.HasVariable(lexemes[pos].Source) && lexemes[pos + 1].Source != "(")
{
var val = new GetVariableElement()
{
VarName = lexemes[pos].Source,
VarType = m_currentFunction.GetVariable(lexemes[pos].Source).VarType,
ResultOfGeneration = GetVariableElement.GenerateOptions.Value
};
++pos;
elem = val;
return(pos);
}
else if (m_symbols.HasFunctionWithName(lexemes[pos].Source))
{
FunctionCallElement callElement = new FunctionCallElement();
string funcName = lexemes[pos].Source;
++pos;
List <ValueElement> values;
if (lexemes[pos + 1].Source == ")") //fucntion without arguments
{
values = new List <ValueElement>();
pos += 2; //'(' ')'
}
else
{
pos = ExtractSeparatedExpressions(lexemes, pos,
flags | ExpressionFlags.AllowAutoDefault,
out values);
}
if (values.Count == 1 && values[0].NumberOfBranches > 1)
{
values = values[0].Children().Select(child => (ValueElement)child).ToList();
}
callElement.FunctionInfo = m_symbols.GetFunction(
funcName,
values.Select(val => val?.ResultType.ResultTypes[0].Name).ToList());
for (int i = 0, end = values.Count; i < end; ++i)
{
if (values[i] == null)
{
values[i] = callElement.FunctionInfo.Arguments[i].DefaultVal;
}
}
callElement.CallArguments = values;
elem = callElement;
return(pos);
}
else if (lexemes[pos].Source == "default")
{
++pos;
if (lexemes[pos].Source == "(")
{
Compilation.Assert(flags.HasFlag(ExpressionFlags.AllowDefaultValue),
"Default type value keyword is used but it isn't allowed here.", lexemes[pos].Line);
++pos; //skip '('
string typeName = lexemes[pos].Source; //TODO: namespaces
ConstValElement constVal = m_symbols.GetDefaultVal(typeName);
elem = new ConstValElement {
Type = constVal.Type, Value = constVal.Value
};
++pos;
++pos; //skip ')'
}
else
{
Compilation.Assert(flags.HasFlag(ExpressionFlags.AllowAutoDefault),
"Auto default keyword is used but it isn't allowed here.", lexemes[pos].Line);
elem = null;
}
return(pos);
}
else //Not a value
{
elem = null;
return(pos);
}
elem = multipleVals;
return(pos);
}