// if_stmt: 'if' expression ':' suite ('elif' expression ':' suite)* ['else' ':' suite]
private IfStatement ParseIfStmt()
{
Eat(TokenKind.KeywordIf);
var itemWhiteSpace = MakeWhiteSpaceList();
if (itemWhiteSpace != null) {
itemWhiteSpace.Add(_tokenWhiteSpace);
}
var start = GetStart();
List<IfStatementTest> l = new List<IfStatementTest>();
l.Add(ParseIfStmtTest());
while (MaybeEat(TokenKind.KeywordElseIf)) {
if (itemWhiteSpace != null) {
itemWhiteSpace.Add(_tokenWhiteSpace);
}
l.Add(ParseIfStmtTest());
}
Statement else_ = null;
string elseWhiteSpace = null;
if (MaybeEat(TokenKind.KeywordElse)) {
elseWhiteSpace = _tokenWhiteSpace;
else_ = ParseSuite();
}
IfStatementTest[] tests = l.ToArray();
IfStatement ret = new IfStatement(tests, else_);
if (_verbatim) {
if(elseWhiteSpace != null) {
AddPreceedingWhiteSpace(ret, elseWhiteSpace);
}
if (itemWhiteSpace != null) {
AddListWhiteSpace(ret, itemWhiteSpace.ToArray());
}
}
ret.SetLoc(start, else_ != null ? else_.EndIndex : tests[tests.Length - 1].EndIndex);
return ret;
}
// IfStmt
public override bool Walk(IfStatement node)
{
BitArray result = new BitArray(_bits.Length, true);
BitArray save = _bits;
_bits = new BitArray(_bits.Length);
foreach (IfStatementTest ist in node.Tests) {
// Set the initial branch value to bits
_bits.SetAll(false);
_bits.Or(save);
// Flow the test first
ist.Test.Walk(this);
// Flow the body
ist.Body.Walk(this);
// Intersect
result.And(_bits);
}
// Set the initial branch value to bits
_bits.SetAll(false);
_bits.Or(save);
if (node.ElseStatement != null) {
// Flow the else_
node.ElseStatement.Walk(this);
}
// Intersect
result.And(_bits);
_bits = save;
// Remember the result
_bits.SetAll(false);
_bits.Or(result);
return false;
}
public override bool Walk(IfStatement node)
{
UpdateChildRanges(node);
if (node.Tests != null) {
foreach (var test in node.Tests) {
var isInstanceNames = GetIsInstanceNamesAndExpressions(test.Test);
if (isInstanceNames != null) {
if (test.Test != null) {
test.Test.Walk(this);
}
if (test.Body != null && !(test.Body is ErrorStatement)) {
Debug.Assert(test.Body is SuiteStatement);
PushIsInstanceScope(test, isInstanceNames, (SuiteStatement)test.Body);
test.Body.Walk(this);
}
} else {
test.Walk(this);
}
}
}
if (node.ElseStatement != null) {
node.ElseStatement.Walk(this);
}
return false;
}
// IfStatement
public override bool Walk(IfStatement node)
{
return ShouldWalkWorker(node);
}
public override void PostWalk(IfStatement node)
{
PostWalkWorker(node);
}
public override bool Walk(IfStatement node)
{
bool allReturn = true;
for (int i = 0; i < node.Tests.Count; i++) {
_raises = Returns = false;
node.Tests[i].Body.Walk(this);
allReturn &= Returns || _raises;
}
_raises = Returns = false;
if (node.ElseStatement != null) {
node.ElseStatement.Walk(this);
allReturn &= Returns || _raises;
} else {
allReturn = false;
}
Returns = allReturn;
return false;
}