ICCItem *fnForLoop (CEvalContext *pCtx, ICCItem *pArguments, DWORD dwData)
// fnForLoop
//
// Evaluates an expression for a given number of iterations
// Iterates from "from" to "to" inclusive.
//
// (for var from to exp)
{
CCodeChain *pCC = pCtx->pCC;
ICCItem *pArgs;
ICCItem *pResult;
ICCItem *pVar;
ICCItem *pBody;
ICCItem *pLocalSymbols;
ICCItem *pOldSymbols;
ICCItem *pError;
int i, iFrom, iTo, iVarOffset;
// Evaluate the arguments and validate them
pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("qiiu"));
if (pArgs->IsError())
return pArgs;
pVar = pArgs->GetElement(0);
iFrom = pArgs->GetElement(1)->GetIntegerValue();
iTo = pArgs->GetElement(2)->GetIntegerValue();
pBody = pArgs->GetElement(3);
// Setup the locals. We start by creating a local symbol table
pLocalSymbols = pCC->CreateSymbolTable();
if (pLocalSymbols->IsError())
{
pArgs->Discard(pCC);
return pLocalSymbols;
}
// Associate the enumaration variable
pError = pLocalSymbols->AddEntry(pCC, pVar, pCC->CreateNil());
if (pError->IsError())
{
pArgs->Discard(pCC);
return pError;
}
pError->Discard(pCC);
// Setup the context
if (pCtx->pLocalSymbols)
pLocalSymbols->SetParent(pCtx->pLocalSymbols);
else
pLocalSymbols->SetParent(pCtx->pLexicalSymbols);
pOldSymbols = pCtx->pLocalSymbols;
pCtx->pLocalSymbols = pLocalSymbols;
// Start with a default result
pResult = pCC->CreateNil();
// Get the offset of the variable so we don't have to
// search for it all the time
iVarOffset = pLocalSymbols->FindOffset(pCC, pVar);
// Loop over all elements of the list
for (i = iFrom; i <= iTo; i++)
{
ICCItem *pItem = pCC->CreateInteger(i);
// Clean up the previous result
pResult->Discard(pCC);
// Set the element
pLocalSymbols->AddByOffset(pCC, iVarOffset, pItem);
pItem->Discard(pCC);
// Eval
pResult = pCC->Eval(pCtx, pBody);
if (pResult->IsError())
break;
}
// Clean up
pCtx->pLocalSymbols = pOldSymbols;
pLocalSymbols->Discard(pCC);
// Done
pArgs->Discard(pCC);
return pResult;
}
ICCItem *fnEnum (CEvalContext *pCtx, ICCItem *pArguments, DWORD dwData)
// fnEnum
//
// Enumerates the elements of a list
//
// (enum list item-var exp)
// (enumwhile list condition item-var exp)
{
CCodeChain *pCC = pCtx->pCC;
ICCItem *pArgs;
ICCItem *pResult;
ICCItem *pVar;
ICCItem *pBody;
ICCItem *pList;
ICCItem *pCondition;
ICCItem *pLocalSymbols;
ICCItem *pOldSymbols;
ICCItem *pError;
int i, iVarOffset;
// Evaluate the arguments and validate them
if (dwData == FN_ENUM_WHILE)
{
pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("vuqu"));
if (pArgs->IsError())
return pArgs;
pList = pArgs->GetElement(0);
pCondition = pArgs->GetElement(1);
pVar = pArgs->GetElement(2);
pBody = pArgs->GetElement(3);
}
else
{
pArgs = pCC->EvaluateArgs(pCtx, pArguments, CONSTLIT("vqu"));
if (pArgs->IsError())
return pArgs;
pList = pArgs->GetElement(0);
pCondition = NULL;
pVar = pArgs->GetElement(1);
pBody = pArgs->GetElement(2);
}
// Setup the locals. We start by creating a local symbol table
pLocalSymbols = pCC->CreateSymbolTable();
if (pLocalSymbols->IsError())
{
pArgs->Discard(pCC);
return pLocalSymbols;
}
// Associate the enumaration variable
pError = pLocalSymbols->AddEntry(pCC, pVar, pCC->CreateNil());
if (pError->IsError())
{
pArgs->Discard(pCC);
return pError;
}
pError->Discard(pCC);
// Setup the context
if (pCtx->pLocalSymbols)
pLocalSymbols->SetParent(pCtx->pLocalSymbols);
else
pLocalSymbols->SetParent(pCtx->pLexicalSymbols);
pOldSymbols = pCtx->pLocalSymbols;
pCtx->pLocalSymbols = pLocalSymbols;
// Start with a default result
pResult = pCC->CreateNil();
// Get the offset of the variable so we don't have to
// search for it all the time
iVarOffset = pLocalSymbols->FindOffset(pCC, pVar);
// Loop over all elements of the list
for (i = 0; i < pList->GetCount(); i++)
{
// Check the condition
if (pCondition)
{
ICCItem *pEval;
// Evaluate the condition
pEval = pCC->Eval(pCtx, pCondition);
if (pEval->IsError())
{
pResult->Discard(pCC);
pResult = pEval;
break;
}
// If the condition is Nil, then we're done
if (pEval->IsNil())
{
pEval->Discard(pCC);
break;
}
}
ICCItem *pItem = pList->GetElement(i);
// Clean up the previous result
pResult->Discard(pCC);
// Set the element
pLocalSymbols->AddByOffset(pCC, iVarOffset, pItem);
// Eval
pResult = pCC->Eval(pCtx, pBody);
if (pResult->IsError())
break;
}
// Clean up
pCtx->pLocalSymbols = pOldSymbols;
pLocalSymbols->Discard(pCC);
// Done
pArgs->Discard(pCC);
return pResult;
}
ICCItem *fnFilter (CEvalContext *pCtx, ICCItem *pArgs, DWORD dwData)
// fnFilter
//
// Filters a list based on a boolean expression.
//
// (filter list var exp) -> list
{
int i;
CCodeChain *pCC = pCtx->pCC;
if (pArgs->GetElement(0)->IsNil())
return pCC->CreateNil();
// Args
ICCItem *pSource = pArgs->GetElement(0);
ICCItem *pVar = pArgs->GetElement(1);
ICCItem *pBody = pArgs->GetElement(2);
// Create a destination list
ICCItem *pResult = pCC->CreateLinkedList();
if (pResult->IsError())
return pResult;
CCLinkedList *pList = (CCLinkedList *)pResult;
// Setup the locals. We start by creating a local symbol table
ICCItem *pLocalSymbols = pCC->CreateSymbolTable();
if (pLocalSymbols->IsError())
{
pResult->Discard(pCC);
return pLocalSymbols;
}
// Associate the enumaration variable
ICCItem *pError = pLocalSymbols->AddEntry(pCC, pVar, pCC->CreateNil());
if (pError->IsError())
{
pLocalSymbols->Discard(pCC);
pResult->Discard(pCC);
return pError;
}
pError->Discard(pCC);
// Setup the context
if (pCtx->pLocalSymbols)
pLocalSymbols->SetParent(pCtx->pLocalSymbols);
else
pLocalSymbols->SetParent(pCtx->pLexicalSymbols);
ICCItem *pOldSymbols = pCtx->pLocalSymbols;
pCtx->pLocalSymbols = pLocalSymbols;
// Get the offset of the variable so we don't have to
// search for it all the time
int iVarOffset = pLocalSymbols->FindOffset(pCC, pVar);
// Loop over all elements of the list
for (i = 0; i < pSource->GetCount(); i++)
{
ICCItem *pItem = pSource->GetElement(i);
// Set the element
pLocalSymbols->AddByOffset(pCC, iVarOffset, pItem);
// Eval
ICCItem *pSelect = pCC->Eval(pCtx, pBody);
if (pSelect->IsError())
{
pResult->Discard(pCC);
pResult = pSelect;
break;
}
// If the evaluation is not Nil, then we include the
// item in the result
if (!pSelect->IsNil())
pList->Append(pCC, pItem, NULL);
pSelect->Discard(pCC);
}
// Clean up
pCtx->pLocalSymbols = pOldSymbols;
pLocalSymbols->Discard(pCC);
// Done
if (pResult->GetCount() > 0)
return pResult;
else
{
pResult->Discard(pCC);
return pCC->CreateNil();
}
}
ICCItem *fnPageMap (CEvalContext *pEvalCtx, ICCItem *pArgs, DWORD dwData)
// fnPageMap
//
// (pageMap address|pageID enumMethod ['excludeNil] var exp) -> filtered list
{
CCodeChain *pCC = pEvalCtx->pCC;
// Args
ICCItem *pAddress = pArgs->GetElement(0);
ICCItem *pMethod = pArgs->GetElement(1);
bool bExcludeNil;
int iOptionalArg = 2;
if (pArgs->GetCount() > 4)
bExcludeNil = strEquals(pArgs->GetElement(iOptionalArg++)->GetStringValue(), CONSTLIT("excludeNil"));
else
bExcludeNil = false;
ICCItem *pVar = pArgs->GetElement(iOptionalArg++);
ICCItem *pBody = pArgs->GetElement(iOptionalArg++);
// Open the page
IPage *pPage;
CString sError;
if (g_PM.OpenPage(pAddress->GetStringValue(), &pPage, &sError) != NOERROR)
return pCC->CreateError(sError, NULL);
// Prepare the method
SPageEnumCtx EnumCtx;
if (pPage->EnumReset(*pCC, pMethod, EnumCtx, &sError))
{
g_PM.ClosePage(pPage);
return pCC->CreateError(sError, NULL);
}
// Create a destination list
ICCItem *pResult = pCC->CreateLinkedList();
if (pResult->IsError())
{
g_PM.ClosePage(pPage);
return pResult;
}
CCLinkedList *pList = (CCLinkedList *)pResult;
// Setup the locals. We start by creating a local symbol table
ICCItem *pLocalSymbols = pCC->CreateSymbolTable();
if (pLocalSymbols->IsError())
{
pResult->Discard(pCC);
g_PM.ClosePage(pPage);
return pLocalSymbols;
}
// Associate the enumaration variable
ICCItem *pError = pLocalSymbols->AddEntry(pCC, pVar, pCC->CreateNil());
if (pError->IsError())
{
pLocalSymbols->Discard(pCC);
pResult->Discard(pCC);
g_PM.ClosePage(pPage);
return pError;
}
pError->Discard(pCC);
// Setup the context
if (pEvalCtx->pLocalSymbols)
pLocalSymbols->SetParent(pEvalCtx->pLocalSymbols);
else
pLocalSymbols->SetParent(pEvalCtx->pLexicalSymbols);
ICCItem *pOldSymbols = pEvalCtx->pLocalSymbols;
pEvalCtx->pLocalSymbols = pLocalSymbols;
// Get the offset of the variable so we don't have to
// search for it all the time
int iVarOffset = pLocalSymbols->FindOffset(pCC, pVar);
// Enumerate the page
while (pPage->EnumHasMore(EnumCtx))
{
ICCItem *pItem = pPage->EnumGetNext(*pCC, EnumCtx);
if (pItem->IsError())
{
pResult->Discard(pCC);
pResult = pItem;
break;
}
// Set the element
pLocalSymbols->AddByOffset(pCC, iVarOffset, pItem);
// Eval
ICCItem *pMapped = pCC->Eval(pEvalCtx, pBody);
if (pMapped->IsError())
{
pItem->Discard(pCC);
pResult->Discard(pCC);
pResult = pMapped;
break;
}
// If the evaluation is not Nil, then we include the
// item in the result
if (!bExcludeNil || !pMapped->IsNil())
pList->Append(*pCC, pMapped);
pItem->Discard(pCC);
pMapped->Discard(pCC);
}
// Clean up
pEvalCtx->pLocalSymbols = pOldSymbols;
pLocalSymbols->Discard(pCC);
g_PM.ClosePage(pPage);
// Done
if (pResult->GetCount() > 0)
return pResult;
else
{
pResult->Discard(pCC);
return pCC->CreateNil();
}
}