// does a for and a quantified expression
// takes the iterator for var expr paris
private void doForExpr(IEnumerator iter, Expr expr)
{
int scopes = 0;
// add variables to scope and check the binding sequence
while (iter.MoveNext())
{
VarExprPair pair = (VarExprPair)iter.Current;
QName @var = pair.varname();
if (!expandVarQName(@var))
{
reportBadPrefix(@var.prefix());
}
Expr e = pair.expr();
e.accept(this);
pushScope(@var, BuiltinTypeLibrary.XS_ANYTYPE);
scopes++;
}
expr.accept(this);
// kill the scopes
for (int i = 0; i < scopes; i++)
{
popScope();
}
}
private void printVarExprPairs(IEnumerator i)
{
while (i.MoveNext())
{
VarExprPair pair = (VarExprPair)i.Current;
QName @var = pair.varname();
Expr e = pair.expr();
e.accept(this);
}
}
// does a for and a quantified expression
// takes the iterator for var expr paris
private void doForExpr(IEnumerator iter, Expr expr)
{
var vars = new ArrayList();
// go through expression and cache variables
while (iter.MoveNext())
{
VarExprPair pair = (VarExprPair)iter.Current;
QName @var = pair.varname();
Expr e = pair.expr();
// XXX this is wrong!
// need to define new scope, and reference "inner scope"
// [shadow outer vars]
/*
* if(_sc.variable_exists(var)) report_error(new
* StaticNameError("Variable " + var.string() +
* " already defined"));
*/
// ok we can cheat here cuz we only care about variable
// "presence" not its specific instance / value so we
// can fakely shadow without creating explicit scopes
// if variable already exists.... then leave it there...
// [we do not need to create a new instance and delete
// it at the end]
// we only need to if variable does not exist
// XXX: i fink this is all wrong
vars.Add(@var);
e.accept(this);
}
// add variables to scope
for (IEnumerator i = vars.GetEnumerator(); i.MoveNext();)
{
QName @var = (QName)i.Current;
}
// do the bounded expression
expr.accept(this);
// remove variables
}
///
/// <param name="qex">
/// is the Quantified expression. </param>
/// <returns> qex expression. </returns>
// XXX: code duplication
public virtual object visit(QuantifiedExpr qex)
{
QuantifiedExpr last = qex;
Expr ret = qex.expr();
int depth = 0;
for (IEnumerator i = qex.iterator(); i.MoveNext();)
{
VarExprPair ve = (VarExprPair)i.Current;
// ok we got nested fors...
if (depth > 0)
{
var pairs = new List <VarExprPair>();
pairs.Add(ve);
QuantifiedExpr qe = new QuantifiedExpr(qex.type(), pairs, ret);
last.set_expr(qe);
last = qe;
}
depth++;
}
// normalize return value, and set it to the last for expr
ret.accept(this);
// get rid of the pairs in the parent (original) for
if (depth > 1)
{
qex.truncate_pairs();
}
return(qex);
}