/// <summary>
/// Tries to eliminate the quotations in a module using parser plugins.
/// It succeeds, then the compiler data of module is set to the simplified
/// module definition.
/// </summary>
private bool EliminateQuotations(bool isQueryContainer, AST <Node> module, List <Flag> flags)
{
var configStack = new Stack <Configuration>();
var success = new SuccessToken();
var simplified = module.Compute <Node>(
(node) =>
{
return(ElimQuoteUnfold(node, configStack, success, flags, cancel));
},
(node, folds) =>
{
return(ElimQuoteFold(node, folds, configStack));
},
cancel);
if (cancel.IsCancellationRequested)
{
return(false);
}
if (success.Result)
{
var modData = new ModuleData(Env, new Location(module), simplified, isQueryContainer);
module.Node.CompilerData = modData;
simplified.CompilerData = modData;
}
return(success.Result);
}
/// <summary>
/// Converts a term AST to a term, and expands symbolic constants as much as possible.
/// Returns null if there are errors.
/// Should only be called after the set has been successfully compiled.
/// </summary>
private Term Expand(AST <Node> ast, List <Flag> flags)
{
bool gotLock = false;
try
{
termIndexLock.Enter(ref gotLock);
UserSymbol other;
var symTable = index.SymbolTable;
var valParamToValue = new Map <UserCnstSymb, Term>(Symbol.Compare);
foreach (var kv in valueInputs)
{
valParamToValue.Add(
(UserCnstSymb)symTable.Resolve(string.Format("%{0}", kv.Key), out other, symTable.ModuleSpace),
kv.Value);
}
var nextDcVarId = new MutableTuple <int>(0);
var success = new SuccessToken();
var symbStack = new Stack <Tuple <Namespace, Symbol> >();
symbStack.Push(new Tuple <Namespace, Symbol>(index.SymbolTable.Root, null));
var result = ast.Compute <Tuple <Term, Term> >(
x => Expand_Unfold(x, symbStack, nextDcVarId, success, flags),
(x, y) => Expand_Fold(x, y, symbStack, valParamToValue, success, flags));
return(result == null ? null : result.Item1);
}
finally
{
if (gotLock)
{
termIndexLock.Exit();
}
}
}
/// <summary>
/// Tries to eliminate the quotations from the AST using the provided configuration.
/// </summary>
internal static Node EliminateQuotations(Configuration config, AST <Node> ast, List <Flag> flags)
{
Contract.Requires(config != null && ast != null && flags != null);
var configStack = new Stack <Configuration>();
var success = new SuccessToken();
configStack.Push(config);
var simplified = ast.Compute <Node>(
(node) =>
{
return(ElimQuoteUnfold(node, configStack, success, flags, default(CancellationToken)));
},
(node, folds) =>
{
return(ElimQuoteFold(node, folds, configStack));
});
return(success.Result ? simplified : null);
}
