StateDeclarationStatement ParseStateDeclaration(TokenRange toks)
{
toks = toks.Consume("state").RevSkipWhile(t => t.Value == ";");
return(new StateDeclarationStatement {
decl = ParseVarDeclaration(toks)
});
}
CodeBlock ParseCodeBlock(TokenRange toks)
{
List <Statement> statements = new List <Statement>();
while (true)
{
Token delim = toks
.FirstOrDefault(
t => t.ParenDepth == toks.First().ParenDepth&&
t.BraceDepth == toks.First().BraceDepth&&
(t.Value == ";" || t.Value == "}")
);
if (delim == null)
{
break;
}
ParseStatement(range(toks.Begin, delim.Position + 1), statements);
toks = range(delim.Position + 1, toks.End);
}
if (!toks.All(Whitespace))
{
throw new Error(toks.First(NonWhitespace).SourceLine, "Trailing unterminated statement in code block");
}
return(new CodeBlock {
statements = statements.ToArray()
});
}
List <Declaration> ParseDescrCodeBlock(TokenRange toks)
{
List <Declaration> declarations = new List <Declaration>();
while (true)
{
Token delim = toks.FirstOrDefault(t => t.Value == ";");
if (delim == null)
{
break;
}
int pos = delim.Position + 1;
var potentialComment = range(pos, toks.End).SkipWhile(t => t.Value == "\t" || t.Value == " ");
if (!potentialComment.IsEmpty && potentialComment.First().Value.StartsWith("//"))
{
pos = potentialComment.First().Position + 1;
}
ParseDeclaration(range(toks.Begin, pos), declarations);
toks = range(pos, toks.End);
}
if (!toks.All(Whitespace))
{
throw new Error(toks.First(NonWhitespace).SourceLine, "Trailing unterminated statement in code block");
}
return(declarations);
}
ChooseStatement ParseChooseStatement(TokenRange toks)
{
return(new ChooseStatement
{
body = ParseCompoundStatement(toks.Consume("choose"))
});
}
Statement ParseTryStatement(TokenRange toks)
{
return(new TryStatement
{
tryBody = ParseCompoundStatement(toks.Consume("try")),
catches = new List <TryStatement.Catch>() // will be filled in later by ParseCatchStatement
});
}
ThrowStatement ParseThrowStatement(TokenRange toks)
{
toks = toks.Consume("throw").RevSkipWhile(t => t.Value == ";");
return(new ThrowStatement
{
expression = str(NormalizeWhitespace(toks))
});
}
public TokenRange GetMatchingRangeIn(TokenRange range)
{
Func <Token, bool> pred;
int dir;
switch (Value)
{
case "(": pred = t => t.Value != ")" || t.ParenDepth != ParenDepth; dir = +1; break;
case ")": pred = t => t.Value != "(" || t.ParenDepth != ParenDepth; dir = -1; break;
case "{": pred = t => t.Value != "}" || t.BraceDepth != BraceDepth; dir = +1; break;
case "}": pred = t => t.Value != "{" || t.BraceDepth != BraceDepth; dir = -1; break;
case "<": return
(new TokenRange(range.GetAllTokens(),
Position + 1,
AngleBracketParser.NotInsideAngleBrackets(
new TokenRange(range.GetAllTokens(), Position, range.End))
.Skip(1) // skip the "<", which is considered "outside"
.First() // get the ">", which is likewise "outside"
.Position));
case "[": return
(new TokenRange(range.GetAllTokens(),
Position + 1,
BracketParser.NotInsideBrackets(
new TokenRange(range.GetAllTokens(), Position, range.End))
.Skip(1) // skip the "[", which is considered "outside"
.First() // get the "]", which is likewise "outside"
.Position));
default: throw new NotSupportedException("Can't match this token!");
}
TokenRange r;
if (dir == -1)
{
r = new TokenRange(range.GetAllTokens(), range.Begin, Position)
.RevTakeWhile(pred);
if (r.Begin == range.Begin)
{
throw new Error(SourceLine, "Syntax error: Unmatched " + Value);
}
}
else
{
r = new TokenRange(range.GetAllTokens(), Position + 1, range.End)
.TakeWhile(pred);
if (r.End == range.End)
{
throw new Error(SourceLine, "Syntax error: Unmatched " + Value);
}
}
return(r);
}
WaitStatement ParseWaitStatement(TokenRange toks)
{
WaitStatement ws = new WaitStatement();
ws.FirstSourceLine = toks.First().SourceLine;
if (toks.First().Value == "state")
{
ws.resultIsState = true;
toks = toks.Consume("state");
}
Token name;
TokenRange type, initializer;
bool constructorSyntax;
ParseDeclaration(toks.RevSkipWhile(t => t.Value == ";"), out name, out type, out initializer, out constructorSyntax);
ws.result = new VarDeclaration
{
name = name.Value,
type = str(NormalizeWhitespace(type)),
initializer = "",
initializerConstructorSyntax = false
};
if (initializer == null)
{
throw new Error(ws.FirstSourceLine, "Wait statement must be a declaration");
}
var waitParams = initializer
.SkipWhile(Whitespace).Consume("Statement contains a wait, but is not a valid wait statement or a supported compound statement.",
t => {
if (t.Value == "wait")
{
return(true);
}
if (t.Value == "waitNext")
{
ws.isWaitNext = true; return(true);
}
return(false);
})
.SkipWhile(Whitespace).First().Assert("Expected (", t => t.Value == "(")
.GetMatchingRangeIn(initializer);
if (!range(waitParams.End, initializer.End).Consume(")").All(Whitespace))
{
throw new Error(toks.First().SourceLine, "Statement contains a wait, but is not a valid wait statement or a supported compound statement.");
}
ws.futureExpression = str(NormalizeWhitespace(waitParams));
return(ws);
}
WhenStatement ParseWhenStatement(TokenRange toks)
{
var expr = toks.Consume("when")
.First(NonWhitespace)
.Assert("Expected (", t => t.Value == "(")
.GetMatchingRangeIn(toks);
return(new WhenStatement {
wait = ParseWaitStatement(expr),
body = ParseCompoundStatement(range(expr.End + 1, toks.End))
});
}
Statement ParseIfStatement(TokenRange toks)
{
var expr = toks.Consume("if")
.First(NonWhitespace)
.Assert("Expected (", t => t.Value == "(")
.GetMatchingRangeIn(toks);
return(new IfStatement {
expression = str(NormalizeWhitespace(expr)),
ifBody = ParseCompoundStatement(range(expr.End + 1, toks.End))
// elseBody will be filled in later if necessary by ParseElseStatement
});
}
WhileStatement ParseWhileStatement(TokenRange toks)
{
var expr = toks.Consume("while")
.First(NonWhitespace)
.Assert("Expected (", t => t.Value == "(")
.GetMatchingRangeIn(toks);
return(new WhileStatement
{
expression = str(NormalizeWhitespace(expr)),
body = ParseCompoundStatement(range(expr.End + 1, toks.End))
});
}
Statement ParseForStatement(TokenRange toks)
{
var head =
toks.Consume("for")
.First(NonWhitespace)
.Assert("Expected (", t => t.Value == "(")
.GetMatchingRangeIn(toks);
Token[] delim =
head.Where(
t => t.ParenDepth == head.First().ParenDepth&&
t.BraceDepth == head.First().BraceDepth&&
t.Value == ";"
).ToArray();
if (delim.Length == 2)
{
var init = range(head.Begin, delim[0].Position);
var cond = range(delim[0].Position + 1, delim[1].Position);
var next = range(delim[1].Position + 1, head.End);
var body = range(head.End + 1, toks.End);
return(new ForStatement
{
initExpression = str(NormalizeWhitespace(init)),
condExpression = str(NormalizeWhitespace(cond)),
nextExpression = str(NormalizeWhitespace(next)),
body = ParseCompoundStatement(body)
});
}
delim =
head.Where(
t => t.ParenDepth == head.First().ParenDepth&&
t.BraceDepth == head.First().BraceDepth&&
t.Value == ":"
).ToArray();
if (delim.Length != 1)
{
throw new Error(head.First().SourceLine, "for statement must be 3-arg style or c++11 2-arg style");
}
return(new RangeForStatement
{
// The container over which to iterate
rangeExpression = str(NormalizeWhitespace(range(delim[0].Position + 1, head.End).SkipWhile(Whitespace))),
// Type and name of the variable assigned in each iteration
rangeDecl = str(NormalizeWhitespace(range(head.Begin, delim[0].Position - 1).SkipWhile(Whitespace))),
// The body of the for loop
body = ParseCompoundStatement(range(head.End + 1, toks.End))
});
}
void ParseDescrHeading(Descr descr, TokenRange toks)
{
toks.First(NonWhitespace).Assert("non-struct DESCR!", t => t.Value == "struct");
toks = toks.SkipWhile(Whitespace).Skip(1).SkipWhile(Whitespace);
var colon = toks.FirstOrDefault(t => t.Value == ":");
if (colon != null)
{
descr.superClassList = str(range(colon.Position + 1, toks.End)).Trim();
toks = range(toks.Begin, colon.Position);
}
descr.name = str(toks).Trim();
}
void ParseElseStatement(TokenRange toks, Statement prevStatement)
{
var ifStatement = prevStatement as IfStatement;
while (ifStatement != null && ifStatement.elseBody != null)
{
ifStatement = ifStatement.elseBody as IfStatement;
}
if (ifStatement == null)
{
throw new Error(toks.First().SourceLine, "else without matching if");
}
ifStatement.elseBody = ParseCompoundStatement(toks.Consume("else"));
}
void ParseDeclaration(TokenRange toks, List <Declaration> declarations)
{
Declaration dec = new Declaration();
Token delim = toks.First(t => t.Value == ";");
var nameRange = range(toks.Begin, delim.Position).RevSkipWhile(Whitespace).RevTakeWhile(NonWhitespace);
var typeRange = range(toks.Begin, nameRange.Begin);
var commentRange = range(delim.Position + 1, toks.End);
dec.name = str(nameRange).Trim();
dec.type = str(typeRange).Trim();
dec.comment = str(commentRange).Trim().TrimStart('/');
declarations.Add(dec);
}
void ParseTestCaseHeading(Actor actor, TokenRange toks)
{
actor.isStatic = true;
// The parameter(s) to the TEST_CASE macro are opaque to the actor compiler
TokenRange paramRange = toks.Last(NonWhitespace)
.Assert("Unexpected tokens after test case parameter list.",
t => t.Value == ")" && t.ParenDepth == toks.First().ParenDepth)
.GetMatchingRangeIn(toks);
actor.testCaseParameters = str(paramRange);
actor.name = "flowTestCase" + toks.First().SourceLine;
actor.parameters = new VarDeclaration[] { };
actor.returnType = "Void";
}
IEnumerable <TokenRange> SplitParameterList(TokenRange toks, string delimiter)
{
if (toks.Begin == toks.End)
{
yield break;
}
while (true)
{
Token comma = AngleBracketParser.NotInsideAngleBrackets(toks)
.FirstOrDefault(t => t.Value == delimiter && t.ParenDepth == toks.First().ParenDepth);
if (comma == null)
{
break;
}
yield return(range(toks.Begin, comma.Position));
toks = range(comma.Position + 1, toks.End);
}
yield return(toks);
}
Statement ParseCompoundStatement(TokenRange toks)
{
var first = toks.First(NonWhitespace);
if (first.Value == "{")
{
var inBraces = first.GetMatchingRangeIn(toks);
if (!range(inBraces.End, toks.End).Consume("}").All(Whitespace))
{
throw new Error(inBraces.Last().SourceLine, "Unexpected tokens after compound statement");
}
return(ParseCodeBlock(inBraces));
}
else
{
List <Statement> statements = new List <Statement>();
ParseStatement(toks.Skip(1), statements);
return(statements[0]);
}
}
void ParseCatchStatement(TokenRange toks, Statement prevStatement)
{
var tryStatement = prevStatement as TryStatement;
if (tryStatement == null)
{
throw new Error(toks.First().SourceLine, "catch without matching try");
}
var expr = toks.Consume("catch")
.First(NonWhitespace)
.Assert("Expected (", t => t.Value == "(")
.GetMatchingRangeIn(toks);
tryStatement.catches.Add(
new TryStatement.Catch
{
expression = str(NormalizeWhitespace(expr)),
body = ParseCompoundStatement(range(expr.End + 1, toks.End)),
FirstSourceLine = expr.First().SourceLine
});
}
void ParseActorHeading(Actor actor, TokenRange toks)
{
var template = toks.First(NonWhitespace);
if (template.Value == "template")
{
var templateParams = range(template.Position + 1, toks.End)
.First(NonWhitespace)
.Assert("Invalid template declaration", t => t.Value == "<")
.GetMatchingRangeIn(toks);
actor.templateFormals = SplitParameterList(templateParams, ",")
.Select(p => ParseVarDeclaration(p)) //< SOMEDAY: ?
.ToArray();
toks = range(templateParams.End + 1, toks.End);
}
var attribute = toks.First(NonWhitespace);
while (attribute.Value == "[")
{
var attributeContents = attribute.GetMatchingRangeIn(toks);
var asArray = attributeContents.ToArray();
if (asArray.Length < 2 || asArray[0].Value != "[" || asArray[asArray.Length - 1].Value != "]")
{
throw new Error(actor.SourceLine, "Invalid attribute: Expected [[...]]");
}
actor.attributes.Add("[" + str(NormalizeWhitespace(attributeContents)) + "]");
toks = range(attributeContents.End + 1, toks.End);
attribute = toks.First(NonWhitespace);
}
var staticKeyword = toks.First(NonWhitespace);
if (staticKeyword.Value == "static")
{
actor.isStatic = true;
toks = range(staticKeyword.Position + 1, toks.End);
}
var uncancellableKeyword = toks.First(NonWhitespace);
if (uncancellableKeyword.Value == "UNCANCELLABLE")
{
actor.SetUncancellable();
toks = range(uncancellableKeyword.Position + 1, toks.End);
}
// Find the parameter list
TokenRange paramRange = toks.Last(NonWhitespace)
.Assert("Unexpected tokens after actor parameter list.",
t => t.Value == ")" && t.ParenDepth == toks.First().ParenDepth)
.GetMatchingRangeIn(toks);
actor.parameters = SplitParameterList(paramRange, ",")
.Select(p => ParseVarDeclaration(p))
.ToArray();
var name = range(toks.Begin, paramRange.Begin - 1).Last(NonWhitespace);
actor.name = name.Value;
// SOMEDAY: refactor?
var returnType = range(toks.First().Position + 1, name.Position).SkipWhile(Whitespace);
var retToken = returnType.First();
if (retToken.Value == "Future")
{
var ofType = returnType.Skip(1).First(NonWhitespace).Assert("Expected <", tok => tok.Value == "<").GetMatchingRangeIn(returnType);
actor.returnType = str(NormalizeWhitespace(ofType));
toks = range(ofType.End + 1, returnType.End);
}
else if (retToken.Value == "void" /* && !returnType.Skip(1).Any(NonWhitespace)*/)
{
actor.returnType = null;
toks = returnType.Skip(1);
}
else
{
throw new Error(actor.SourceLine, "Actor apparently does not return Future<T>");
}
toks = toks.SkipWhile(Whitespace);
if (!toks.IsEmpty)
{
if (toks.Last().Value == "::")
{
actor.nameSpace = str(range(toks.Begin, toks.End - 1));
}
else
{
Console.WriteLine("Tokens: '{0}' {1} '{2}'", str(toks), toks.Count(), toks.Last().Value);
throw new Error(actor.SourceLine, "Unrecognized tokens preceding parameter list in actor declaration");
}
}
if (errorMessagePolicy.ActorsNoDiscardByDefault() && !actor.attributes.Contains("[[flow_allow_discard]]"))
{
if (actor.IsCancellable())
{
actor.attributes.Add("[[nodiscard]]");
}
}
HashSet <string> knownFlowAttributes = new HashSet <string>();
knownFlowAttributes.Add("[[flow_allow_discard]]");
foreach (var flowAttribute in actor.attributes.Where(a => a.StartsWith("[[flow_")))
{
if (!knownFlowAttributes.Contains(flowAttribute))
{
throw new Error(actor.SourceLine, "Unknown flow attribute {0}", flowAttribute);
}
}
actor.attributes = actor.attributes.Where(a => !a.StartsWith("[[flow_")).ToList();
}
void ParseStatement(TokenRange toks, List <Statement> statements)
{
toks = toks.SkipWhile(Whitespace);
Action <Statement> Add = stmt =>
{
stmt.FirstSourceLine = toks.First().SourceLine;
statements.Add(stmt);
};
switch (toks.First().Value)
{
case "loop": Add(ParseLoopStatement(toks)); break;
case "while": Add(ParseWhileStatement(toks)); break;
case "for": Add(ParseForStatement(toks)); break;
case "break": Add(new BreakStatement()); break;
case "continue": Add(new ContinueStatement()); break;
case "return": Add(ParseReturnStatement(toks)); break;
case "{": Add(ParseCompoundStatement(toks)); break;
case "if": Add(ParseIfStatement(toks)); break;
case "else": ParseElseStatement(toks, statements[statements.Count - 1]); break;
case "choose": Add(ParseChooseStatement(toks)); break;
case "when": Add(ParseWhenStatement(toks)); break;
case "try": Add(ParseTryStatement(toks)); break;
case "catch": ParseCatchStatement(toks, statements[statements.Count - 1]); break;
case "throw": Add(ParseThrowStatement(toks)); break;
default:
if (IllegalKeywords.Contains(toks.First().Value))
{
throw new Error(toks.First().SourceLine, "Statement '{0}' not supported in actors.", toks.First().Value);
}
if (toks.Any(t => t.Value == "wait" || t.Value == "waitNext"))
{
Add(ParseWaitStatement(toks));
}
else if (toks.First().Value == "state")
{
Add(ParseStateDeclaration(toks));
}
else if (toks.First().Value == "switch" && toks.Any(t => t.Value == "return"))
{
throw new Error(toks.First().SourceLine, "Unsupported compound statement containing return.");
}
else if (toks.RevSkipWhile(t => t.Value == ";").Any(NonWhitespace))
{
Add(new PlainOldCodeStatement
{
code = str(NormalizeWhitespace(toks.RevSkipWhile(t => t.Value == ";"))) + ";"
});
}
break;
}
;
}
IEnumerable <Token> NormalizeWhitespace(IEnumerable <Token> tokens)
{
bool inWhitespace = false;
bool leading = true;
foreach (var tok in tokens)
{
if (!tok.IsWhitespace)
{
if (inWhitespace && !leading)
{
yield return new Token {
Value = " "
}
}
;
inWhitespace = false;
yield return(tok);
leading = false;
}
else
{
inWhitespace = true;
}
}
}
void ParseDeclaration(TokenRange tokens,
out Token name,
out TokenRange type,
out TokenRange initializer,
out bool constructorSyntax)
{
initializer = null;
TokenRange beforeInitializer = tokens;
constructorSyntax = false;
Token equals = AngleBracketParser.NotInsideAngleBrackets(tokens)
.FirstOrDefault(t => t.Value == "=" && t.ParenDepth == tokens.First().ParenDepth);
if (equals != null)
{
// type name = initializer;
beforeInitializer = range(tokens.Begin, equals.Position);
initializer = range(equals.Position + 1, tokens.End);
}
else
{
Token paren = AngleBracketParser.NotInsideAngleBrackets(tokens)
.FirstOrDefault(t => t.Value == "(");
if (paren != null)
{
// type name(initializer);
constructorSyntax = true;
beforeInitializer = range(tokens.Begin, paren.Position);
initializer =
range(paren.Position + 1, tokens.End)
.TakeWhile(t => t.ParenDepth > paren.ParenDepth);
}
}
name = beforeInitializer.Last(NonWhitespace);
if (beforeInitializer.Begin == name.Position)
{
throw new Error(beforeInitializer.First().SourceLine, "Declaration has no type.");
}
type = range(beforeInitializer.Begin, name.Position);
}
VarDeclaration ParseVarDeclaration(TokenRange tokens)
{
Token name;
TokenRange type, initializer;
bool constructorSyntax;
ParseDeclaration(tokens, out name, out type, out initializer, out constructorSyntax);
return(new VarDeclaration
{
name = name.Value,
type = str(NormalizeWhitespace(type)),
initializer = initializer == null ? "" : str(NormalizeWhitespace(initializer)),
initializerConstructorSyntax = constructorSyntax
});
}
void ParseActorHeading(Actor actor, TokenRange toks)
{
var template = toks.First(NonWhitespace);
if (template.Value == "template")
{
var templateParams = range(template.Position + 1, toks.End)
.First(NonWhitespace)
.Assert("Invalid template declaration", t => t.Value == "<")
.GetMatchingRangeIn(toks);
actor.templateFormals = SplitParameterList(templateParams, ",")
.Select(p => ParseVarDeclaration(p)) //< SOMEDAY: ?
.ToArray();
toks = range(templateParams.End + 1, toks.End);
}
var staticKeyword = toks.First(NonWhitespace);
if (staticKeyword.Value == "static")
{
actor.isStatic = true;
toks = range(staticKeyword.Position + 1, toks.End);
}
var uncancellableKeyword = toks.First(NonWhitespace);
if (uncancellableKeyword.Value == "UNCANCELLABLE")
{
actor.isUncancellable = true;
toks = range(uncancellableKeyword.Position + 1, toks.End);
}
// Find the parameter list
TokenRange paramRange = toks.Last(NonWhitespace)
.Assert("Unexpected tokens after actor parameter list.",
t => t.Value == ")" && t.ParenDepth == toks.First().ParenDepth)
.GetMatchingRangeIn(toks);
actor.parameters = SplitParameterList(paramRange, ",")
.Select(p => ParseVarDeclaration(p))
.ToArray();
var name = range(toks.Begin, paramRange.Begin - 1).Last(NonWhitespace);
actor.name = name.Value;
// SOMEDAY: refactor?
var returnType = range(toks.First().Position + 1, name.Position).SkipWhile(Whitespace);
var retToken = returnType.First();
if (retToken.Value == "Future")
{
var ofType = returnType.Skip(1).First(NonWhitespace).Assert("Expected <", tok => tok.Value == "<").GetMatchingRangeIn(returnType);
actor.returnType = str(NormalizeWhitespace(ofType));
toks = range(ofType.End + 1, returnType.End);
}
else if (retToken.Value == "void" /* && !returnType.Skip(1).Any(NonWhitespace)*/)
{
actor.returnType = null;
toks = returnType.Skip(1);
}
else
{
throw new Error(actor.SourceLine, "Actor apparently does not return Future<T>");
}
toks = toks.SkipWhile(Whitespace);
if (!toks.IsEmpty)
{
if (toks.Last().Value == "::")
{
actor.nameSpace = str(range(toks.Begin, toks.End - 1));
}
else
{
Console.WriteLine("Tokens: '{0}' {1} '{2}'", str(toks), toks.Count(), toks.Last().Value);
throw new Error(actor.SourceLine, "Unrecognized tokens preceding parameter list in actor declaration");
}
}
}
LoopStatement ParseLoopStatement(TokenRange toks)
{
return(new LoopStatement {
body = ParseCompoundStatement(toks.Consume("loop"))
});
}