/*
* (non-Javadoc)
*
* @see com.ibm.jaql.lang.rewrite.Rewrite#rewrite(com.ibm.jaql.lang.expr.core.Expr)
*/
@Override
public boolean rewrite(Expr expr) {
assert expr instanceof InlinePragma;
Expr c = expr.child(0);
if (c instanceof VarExpr) {
VarExpr varExpr = (VarExpr) c;
Var var = varExpr.var();
Expr def = varExpr.findVarDef();
// // TODO: I think this case is gone now; function parameters are in bindings that are
// found.
// if (def == null)
// {
// // must be a function parameter // TODO: findVarDef SHOULD find it, and params
// should use Bindings
// return false;
// }
if (def instanceof BindingExpr) {
BindingExpr b = (BindingExpr) def;
assert var == b.var; // or else findDef is broken
Expr p = def.parent();
if (p instanceof DoExpr) {
expr.replaceInParent(cloneExpr(b.eqExpr()));
return true;
}
// else if( p instanceof DefineFunctionExpr )
// We couldn't inline, yet...
return false;
} else // TODO: I don't think this case arises anymore...
{
assert false;
return false;
// assert var.isGlobal();
// Expr replaceBy;
// if (var.value != null)
// {
// // If the global is already computed, inline its value
// replaceBy = new ConstExpr(var.value);
// }
// else
// {
// // If the global is not already computed, inline its expr
// replaceBy = cloneExpr(def);
// }
// expr.replaceInParent(replaceBy);
// return true;
}
}
// If this inline request is not over a VarExpr, just remove it.
expr.replaceInParent(c);
return true;
}
/*
* (non-Javadoc)
*
* @see com.ibm.jaql.lang.rewrite.Rewrite#rewrite(com.ibm.jaql.lang.expr.core.Expr)
*/
@Override
public boolean rewrite(Expr expr) {
ForExpr fe = (ForExpr) expr;
Expr inExpr = fe.binding().inExpr();
Expr c = fe.collectExpr();
// for( i in [] ) e => []
// for( i in null ) e => []
// for( i in e ) [] => []
// for( i in e ) null => []
// TODO: was this, but it ran slowly: if (inExpr.getSchema().isEmpty(ARRAY,NULL).always() ||
// c.getSchema().isEmpty(ARRAY,NULL).always())
if (isEmptyArrayOrNull(inExpr) || isEmptyArrayOrNull(c)) {
fe.replaceInParent(new ArrayExpr());
return true;
}
// look for collect [$i]
if (!(c instanceof ArrayExpr) || c.numChildren() != 1) {
return false;
}
c = c.child(0);
// for( $i in e1 ) [$i] => asArray(e1) => e1 (when non-null array)
if (c instanceof VarExpr) {
VarExpr ve = (VarExpr) c;
if (ve.var() == fe.var()) {
if (inExpr.getSchema().is(ARRAY, NULL).maybeNot() || inExpr.getSchema().is(NULL).maybe()) {
inExpr = new AsArrayFn(inExpr);
}
fe.replaceInParent(inExpr);
return true;
}
}
// e1 -> expand [e2] ==> e1 -> transform e2
expr = new TransformExpr(fe.binding(), c);
fe.replaceInParent(expr);
return true;
}