//-----------------------------------------------------------
private Type Visit(ForStatement node, Table table)
{
LoopNestingLevel++;
Type varType = Visit((dynamic)node[0], table);
var varName = node[0].AnchorToken.Lexeme;
GlobalSymbolTable gstable = table as GlobalSymbolTable;
LocalSymbolTable lstable = table as LocalSymbolTable;
if (table is GlobalSymbolTable)
{
if (gstable[varName].IsConstant)
{
throw new SemanticError("Loop variable " + varName + " cannot be a constant", node[0].AnchorToken);
}
}
else
{
if (lstable.Contains(varName))
{
if (lstable[varName].Kind != Clasification.VAR)
{
throw new SemanticError("Loop variable " + varName + " cannot be a constant or parameter", node[0].AnchorToken);
}
}
else
{
if (GSTable[varName].IsConstant)
{
throw new SemanticError("Loop variable " + varName + " cannot be a constant", node[0].AnchorToken);
}
}
}
Type iterableType = Visit((dynamic)node[1], table);
if (iterableType == Type.LIST_OF_BOOLEAN)
{
if (varType != Type.BOOLEAN)
{
throw new SemanticError("Incorrect loop variable \"" + varName + "\". Expecting " + Type.BOOLEAN + ", but found " + varType, node[0].AnchorToken);
}
}
else if (iterableType == Type.LIST_OF_INTEGER)
{
if (varType != Type.INTEGER)
{
throw new SemanticError("Incorrect loop variable \"" + varName + "\". Expecting " + Type.INTEGER + ", but found " + varType, node[0].AnchorToken);
}
}
else if (iterableType == Type.LIST_OF_STRING)
{
if (varType != Type.STRING)
{
throw new SemanticError("Incorrect loop variable \"" + varName + "\". Expecting " + Type.STRING + ", but found " + varType, node[0].AnchorToken);
}
}
else
{
throw new SemanticError("Loop can only iterate over list types, but found " + iterableType, node[1].AnchorToken);
}
for (var i = 2; i < node.Count(); i++)
{
Visit((dynamic)node[i], table);
}
LoopNestingLevel--;
return(Type.VOID);
}
