private EnumVariantSyntax ParseEnumVariant()
{
var identifier = Tokens.RequiredToken <IIdentifierToken>();
// TODO we actually expect commas separating them, need to improve this
var comma = Tokens.AcceptToken <ICommaToken>();
return(new EnumVariantSyntax(identifier.Value));
}
private ITypeSyntax ParseTypeWithCapability <TCapabilityToken>(ReferenceCapability immutableCapability, ReferenceCapability mutableCapability)
where TCapabilityToken : ICapabilityToken
{
var primaryCapability = Tokens.RequiredToken <TCapabilityToken>();
var mutableKeyword = Tokens.AcceptToken <IMutableKeywordToken>();
var referent = ParseBareType();
var span = TextSpan.Covering(primaryCapability.Span, referent.Span);
var capability = mutableKeyword is null ? immutableCapability : mutableCapability;
return(new CapabilityTypeSyntax(capability, referent, span));
}
private AccessModifier?AcceptFieldGetter()
{
// TODO allow other access modifiers
var publicKeyword = Tokens.AcceptToken <IPublicKeywordToken>();
var getKeyword = Tokens.AcceptToken <IGetKeywordToken>();
if (publicKeyword == null && getKeyword == null)
{
return(null);
}
return(AccessModifier.Public);
}
public ParameterSyntax ParseParameter()
{
switch (Tokens.Current)
{
case IRefKeywordToken _:
case IMutableKeywordToken _:
case ISelfKeywordToken _:
{
var span = Tokens.Current.Span;
var refSelf = Tokens.Accept <IRefKeywordToken>();
var mutableSelf = Tokens.Accept <IMutableKeywordToken>();
var selfSpan = Tokens.Expect <ISelfKeywordToken>();
span = TextSpan.Covering(span, selfSpan);
var name = nameContext.Qualify(SpecialName.Self);
return(new SelfParameterSyntax(span, name, refSelf, mutableSelf));
}
case IDotToken _:
{
var dot = Tokens.Expect <IDotToken>();
var identifier = Tokens.RequiredToken <IIdentifierToken>();
var equals = Tokens.AcceptToken <IEqualsToken>();
ExpressionSyntax defaultValue = null;
if (equals != null)
{
defaultValue = ParseExpression();
}
var span = TextSpan.Covering(dot, identifier.Span, defaultValue?.Span);
var name = nameContext.Qualify(SimpleName.Special("field_" + identifier.Value));
return(new FieldParameterSyntax(span, name, defaultValue));
}
default:
{
var span = Tokens.Current.Span;
var isParams = Tokens.Accept <IParamsKeywordToken>();
var mutableBinding = Tokens.Accept <IVarKeywordToken>();
var identifier = Tokens.RequiredToken <IIdentifierOrUnderscoreToken>();
var name = nameContext.Qualify(variableNumbers.VariableName(identifier.Value));
Tokens.Expect <IColonToken>();
// Need to not consume the assignment that separates the type from the default value,
// hence the min operator precedence.
var type = ParseExpression(OperatorPrecedence.AboveAssignment);
ExpressionSyntax defaultValue = null;
if (Tokens.Accept <IEqualsToken>())
{
defaultValue = ParseExpression();
}
span = TextSpan.Covering(span, type.Span, defaultValue?.Span);
return(new NamedParameterSyntax(span, isParams, mutableBinding, name, type, defaultValue));
}
}
}
public ITypeSyntax ParseType()
{
var typeSyntax = ParseTypeWithCapability();
IQuestionToken?question;
while ((question = Tokens.AcceptToken <IQuestionToken>()) != null)
{
var span = TextSpan.Covering(typeSyntax.Span, question.Span);
return(new OptionalTypeSyntax(span, typeSyntax));
}
return(typeSyntax);
}
public UsingDirectiveSyntax AcceptUsingDirective()
{
if (!Tokens.Accept <IUsingKeywordToken>())
{
return(null);
}
var identifiers = AcceptOneOrMore <IIdentifierToken, IDotToken>(
() => Tokens.AcceptToken <IIdentifierToken>());
RootName name = GlobalNamespaceName.Instance;
foreach (var identifier in identifiers)
{
name = name.Qualify(identifier.Value);
}
Tokens.Expect <ISemicolonToken>();
return(new UsingDirectiveSyntax((Name)name));
}
public GenericParameterSyntax ParseGenericParameter()
{
Name name;
var dollar = Tokens.AcceptToken <IDollarToken>();
if (dollar != null)
{
var lifetime = Tokens.RequiredToken <ILifetimeNameToken>();
var span = TextSpan.Covering(dollar.Span, lifetime.Span);
switch (lifetime)
{
case IIdentifierToken lifetimeIdentifier:
name = nameContext.Qualify(lifetimeIdentifier.Value);
break;
case IRefKeywordToken _:
name = nameContext.Qualify(SpecialName.Ref);
break;
case IOwnedKeywordToken _:
Add(ParseError.OwnedNotValidAsGenericLifetimeParameter(File, span));
// We just treat it as if they had written `$\owned`
name = nameContext.Qualify("owned");
break;
default:
throw NonExhaustiveMatchException.For(lifetime);
}
return(new GenericParameterSyntax(true, false, name, null));
}
var isParams = Tokens.Accept <IParamsKeywordToken>();
var identifier = Tokens.RequiredToken <IIdentifierToken>();
name = nameContext.Qualify(identifier.Value);
ExpressionSyntax typeExpression = null;
if (Tokens.Accept <IColonToken>())
{
typeExpression = ParseExpression();
}
return(new GenericParameterSyntax(false, isParams, name, typeExpression));
}
internal NamespaceDeclarationSyntax ParseNamespaceDeclaration(
ModifierParser modifiers)
{
modifiers.ParseEndOfModifiers();
var ns = Tokens.Expect <INamespaceKeywordToken>();
var globalQualifier = Tokens.AcceptToken <IColonColonDotToken>();
var(name, nameSpan) = ParseNamespaceName();
nameSpan = TextSpan.Covering(nameSpan, globalQualifier?.Span);
Tokens.Expect <IOpenBraceToken>();
var bodyParser = NamespaceBodyParser(name);
var usingDirectives = bodyParser.ParseUsingDirectives();
var declarations = bodyParser.ParseNonMemberDeclarations <ICloseBraceToken>();
var closeBrace = Tokens.Expect <ICloseBraceToken>();
var span = TextSpan.Covering(ns, closeBrace);
return(new NamespaceDeclarationSyntax(ContainingNamespace, span, File, globalQualifier != null, name, nameSpan, usingDirectives, declarations));
}
public NamespaceDeclarationSyntax ParseNamespaceDeclaration(
FixedList <AttributeSyntax> attributes,
FixedList <IModiferToken> modifiers)
{
// TODO generate errors for attributes or modifiers
Tokens.Expect <INamespaceKeywordToken>();
var globalQualifier = Tokens.AcceptToken <IColonColonToken>();
var(name, span) = ParseNamespaceName();
span = TextSpan.Covering(span, globalQualifier?.Span);
Tokens.Expect <IOpenBraceToken>();
var bodyParser = NestedParser(nameContext.Qualify(name));
var usingDirectives = bodyParser.ParseUsingDirectives();
var declarations = bodyParser.ParseDeclarations();
Tokens.Expect <ICloseBraceToken>();
return(new NamespaceDeclarationSyntax(File, globalQualifier != null, name, span,
nameContext, usingDirectives, declarations));
}
private (ITypeSyntax?Type, bool InferMutableType) ParseVariableDeclarationType()
{
var mutableKeyword = Tokens.AcceptToken <IMutableKeywordToken>();
if (mutableKeyword is null)
{
return(ParseType(), false);
}
switch (Tokens.Current)
{
case IEqualsToken _:
case ISemicolonToken _:
return(null, true);
default:
return(ParseMutableType(mutableKeyword), false);
}
}
public InitializerDeclarationSyntax ParseInitializer(
FixedList <AttributeSyntax> attributes,
FixedList <IModiferToken> modifiers)
{
var initKeywordSpan = Tokens.Expect <IInitKeywordToken>();
var identifier = Tokens.AcceptToken <IIdentifierToken>();
var name = nameContext.Qualify(SimpleName.Special("init" + (identifier != null ? "_" + identifier.Value : "")));
var bodyParser = NestedParser(name);
var genericParameters = AcceptGenericParameters();
var parameters = bodyParser.ParseParameters();
var genericConstraints = ParseGenericConstraints();
var mayEffects = ParseMayEffects();
var noEffects = ParseNoEffects();
var(requires, ensures) = ParseFunctionContracts();
var body = bodyParser.ParseBlock();
return(new InitializerDeclarationSyntax(File, modifiers, name,
TextSpan.Covering(initKeywordSpan, identifier?.Span), genericParameters, parameters,
genericConstraints, mayEffects, noEffects, requires, ensures, body));
}
internal ConstructorDeclarationSyntax ParseConstructor(
IClassDeclarationSyntax declaringType,
ModifierParser modifiers)
{
var accessModifer = modifiers.ParseAccessModifier();
modifiers.ParseEndOfModifiers();
var newKeywordSpan = Tokens.Expect <INewKeywordToken>();
var identifier = Tokens.AcceptToken <IIdentifierToken>();
Name?name = identifier is null ? null : (Name)identifier.Value;
var bodyParser = BodyParser();
// Implicit self parameter is taken to be after the current token which is expected to be `(`
var selfParameter = new SelfParameterSyntax(Tokens.Current.Span.AtEnd(), true);
var parameters = bodyParser.ParseParameters(bodyParser.ParseConstructorParameter);
var body = bodyParser.ParseFunctionBody();
// For now, just say constructors have no annotations
var reachabilityAnnotations = new ReachabilityAnnotationsSyntax(Tokens.Current.Span.AtStart(), null, null);
var span = TextSpan.Covering(newKeywordSpan, body.Span);
return(new ConstructorDeclarationSyntax(declaringType, span, File, accessModifer,
TextSpan.Covering(newKeywordSpan, identifier?.Span), name, selfParameter, parameters, reachabilityAnnotations, body));
}
public IConstructorParameterSyntax ParseConstructorParameter()
{
switch (Tokens.Current)
{
case IDotToken _:
{
var dot = Tokens.Expect <IDotToken>();
var identifier = Tokens.RequiredToken <IIdentifierToken>();
var equals = Tokens.AcceptToken <IEqualsToken>();
IExpressionSyntax?defaultValue = null;
if (equals != null)
{
defaultValue = ParseExpression();
}
var span = TextSpan.Covering(dot, identifier.Span, defaultValue?.Span);
Name name = identifier.Value;
return(new FieldParameterSyntax(span, name, defaultValue));
}
default:
return(ParseFunctionParameter());
}
}
public IUsingDirectiveSyntax?AcceptUsingDirective()
{
var accept = Tokens.AcceptToken <IUsingKeywordToken>();
if (accept is null)
{
return(null);
}
var identifiers = ParseManySeparated <(IIdentifierToken?, TextSpan), IDotToken>(
() => Tokens.ExpectToken <IIdentifierToken>());
NamespaceName name = NamespaceName.Global;
foreach (var(identifier, _) in identifiers)
{
if (!(identifier is null))
{
name = name.Qualify(identifier.Value);
}
}
var semicolon = Tokens.Expect <ISemicolonToken>();
var span = TextSpan.Covering(accept.Span, semicolon);
return(new UsingDirectiveSyntax(span, name));
}