public AstBlock(AstBlockType type, IAstNode condition = null)
{
Type = type;
Condition = condition;
_nodes = new LinkedList <IAstNode>();
}
private static bool BlockMatches(IAstNode node, AstBlockType type, IAstNode cond)
{
if (!(node is AstBlock block))
{
return(false);
}
return(block.Type == type && IsSameCond(block.Condition, cond));
}
private static AstBlock Enclose(
AstBlock block,
AstBlockType type,
IAstNode cond,
IAstNode first,
IAstNode last = null)
{
if (first == last)
{
return(null);
}
if (type == AstBlockType.If)
{
cond = InverseCond(cond);
}
// Do a quick check, if we are enclosing a single block,
// and the block type/condition matches the one we're going
// to create, then we don't need a new block, we can just
// return the old one.
bool hasSingleNode = Next(first) == last;
if (hasSingleNode && BlockMatches(first, type, cond))
{
return(first as AstBlock);
}
AstBlock newBlock = new AstBlock(type, cond);
block.AddBefore(first, newBlock);
while (first != last)
{
IAstNode next = Next(first);
block.Remove(first);
newBlock.Add(first);
first = next;
}
return(newBlock);
}
