static CodeStatement _ParseStatement(_PC pc, bool includeComments = false)
{
#region Preamble
CodeLinePragma lp = null;
var startDirs = new CodeDirectiveCollection();
while (ST.directive == pc.SymbolId)
{
var d = _ParseDirective(pc);
if (null != d)
{
var clp = d as CodeLinePragma;
if (null != clp)
{
lp = clp;
}
else
{
startDirs.Add(d as CodeDirective);
}
}
while (!includeComments && ST.lineComment == pc.SymbolId || ST.blockComment == pc.SymbolId)
{
pc.Advance(false);
}
}
CodeStatement stmt = null;
if (includeComments && (ST.lineComment == pc.SymbolId || ST.blockComment == pc.SymbolId))
{
stmt = _ParseCommentStatement(pc);
stmt.StartDirectives.AddRange(startDirs);
if (null != lp)
{
stmt.LinePragma = lp;
}
}
else
{
while (ST.lineComment == pc.SymbolId || ST.blockComment == pc.SymbolId)
{
pc.Advance(false);
}
}
#endregion Preamble
var l = pc.Line;
var c = pc.Column;
var p = pc.Position;
// if we got here we've parsed our start directives and this isn't a comment statement
if (null == stmt)
{
_PC pc2 = null;
switch (pc.SymbolId)
{
case ST.semi:
// can't do much with empty statements
pc.Advance();
stmt = new CodeSnippetStatement().SetLoc(l, c, p);
break;
case ST.gotoKeyword:
pc.Advance();
if (ST.identifier != pc.SymbolId)
{
pc.Error("Expecting label identifier in goto statement");
}
stmt = new CodeGotoStatement(pc.Value).SetLoc(l, c, p);
if (ST.semi != pc.SymbolId)
{
pc.Error("Expecting ; in goto statement");
}
pc.Advance();
break;
case ST.returnKeyword:
pc.Advance();
if (ST.semi != pc.SymbolId)
{
stmt = new CodeMethodReturnStatement(_ParseExpression(pc)).Mark(l, c, p);
}
else
{
stmt = new CodeMethodReturnStatement().SetLoc(l, c, p);
}
if (ST.semi != pc.SymbolId)
{
pc.Error("Expecting ; in return statement");
}
pc.Advance();
break;
case ST.throwKeyword:
pc.Advance();
var expr = _ParseExpression(pc);
stmt = new CodeThrowExceptionStatement(expr).Mark(l, c, p);
if (ST.semi != pc.SymbolId)
{
pc.Error("Expecting ; in throw statement");
}
pc.Advance();
break;
case ST.ifKeyword:
stmt = _ParseIfStatement(pc);
break;
case ST.whileKeyword:
stmt = _ParseWhileStatement(pc);
break;
case ST.forKeyword:
stmt = _ParseForStatement(pc);
break;
case ST.tryKeyword:
stmt = _ParseTryCatchFinallyStatement(pc);
break;
case ST.varType:
stmt = _ParseVariableDeclarationStatement(pc);
break;
default:
// possibly a var decl, a label statement, or an expression statement
if (ST.identifier == pc.SymbolId)
{
pc2 = pc.GetLookAhead(true);
pc2.Advance();
if (ST.colon == pc2.SymbolId) // label
{
var lbl = pc2.Value;
pc.Advance();
stmt = new CodeLabeledStatement(lbl, new CodeSnippetStatement().SetLoc(l, c, p)).SetLoc(l, c, p);
pc2 = null;
break;
}
}
pc2 = null;
pc2 = pc.GetLookAhead(true);
pc2.ResetAdvanceCount();
var advc = 0;
try
{
// possibly a var decl
stmt = _ParseVariableDeclarationStatement(pc2);
advc = pc2.AdvanceCount;
while (advc > 0)
{
pc.Advance(false);
--advc;
}
break;
}
catch (SlangSyntaxException sx)
{
try
{
pc.ResetAdvanceCount();
expr = _ParseExpression(pc);
if (ST.semi != pc.SymbolId)
{
pc.Error("Expecting ; in expression statement");
}
pc.Advance();
var bo = expr as CodeBinaryOperatorExpression;
if (null != bo && CodeBinaryOperatorType.Assign == bo.Operator)
{
var ur = bo.UserData.Contains("slang:unresolved");
stmt = new CodeAssignStatement(bo.Left, bo.Right).Mark(l, c, p, ur);
}
else
{
stmt = new CodeExpressionStatement(expr).Mark(l, c, p);
}
break;
}
catch (SlangSyntaxException sx2)
{
if (pc.AdvanceCount > advc)
{
throw sx2;
}
throw sx;
}
}
}
}
#region Post
stmt.StartDirectives.AddRange(startDirs);
if (null != lp)
{
stmt.LinePragma = lp;
}
while (!includeComments && ST.lineComment == pc.SymbolId || ST.blockComment == pc.SymbolId)
{
pc.Advance(false);
}
while (ST.directive == pc.SymbolId && pc.Value.StartsWith("#end", StringComparison.InvariantCulture))
{
stmt.EndDirectives.Add(_ParseDirective(pc) as CodeDirective);
while (!includeComments && ST.lineComment == pc.SymbolId || ST.blockComment == pc.SymbolId)
{
pc.Advance(false);
}
}
#endregion Post
return(stmt);
}
