private void ParseGenericMethodParameterConstraints(SpecSharpGenericMethodParameterDeclaration applicableParameter, TokenSet followers)
//^ ensures followers[this.currentToken] || this.currentToken == Token.EndOfFile;
{
TokenSet constraintStart = Parser.IdentifierOrNonReservedKeyword|Token.Struct|Token.Class|Token.New;
if (!constraintStart[this.currentToken]) {
this.HandleError(Error.TypeExpected);
this.SkipTo(followers);
return;
}
if (this.currentToken == Token.Class) {
this.GetNextToken();
applicableParameter.MustBeReferenceType = true;
} else if (this.currentToken == Token.Struct) {
this.GetNextToken();
applicableParameter.MustBeValueType = true;
}
while (constraintStart[this.currentToken]) {
//^ assume this.currentToken != Token.EndOfFile;
if (this.currentToken == Token.Class || this.currentToken == Token.Struct) {
this.HandleError(Error.RefValBoundMustBeFirst);
this.GetNextToken(); continue;
} else if (this.currentToken == Token.New) {
this.GetNextToken();
this.Skip(Token.LeftParenthesis);
this.Skip(Token.RightParenthesis);
applicableParameter.MustHaveDefaultConstructor = true;
if (this.currentToken == Token.Comma) {
this.HandleError(Error.NewBoundMustBeLast);
}
break;
}
applicableParameter.AddConstraint(this.ParseTypeExpression(false, false, constraintStart|Token.Comma|followers));
if (this.currentToken != Token.Comma) break;
this.GetNextToken();
}
this.SkipTo(followers);
}
private void ParseGenericMethodParameterConstraintsClauses(List<Ast.GenericMethodParameterDeclaration> genericMethodParameters, TokenSet followers)
// ^ requires forall{Ast.GenericMethodParameterDeclaration genericMethodParameter in genericMethodParameters; genericMethodParameter is SpecSharpGenericMethodParameterDeclaration};
//^ ensures followers[this.currentToken] || this.currentToken == Token.EndOfFile;
{
while (this.currentToken == Token.Where) {
this.GetNextToken();
if (!Parser.IdentifierOrNonReservedKeyword[this.currentToken])
this.HandleError(Error.ExpectedIdentifier);
NameDeclaration name = this.ParseNameDeclaration();
SpecSharpGenericMethodParameterDeclaration/*?*/ applicableParameter = null;
foreach (Ast.GenericMethodParameterDeclaration genericMethodParameter in genericMethodParameters)
if (genericMethodParameter.Name.UniqueKey == name.UniqueKey) {
//^ assume genericMethodParameter is SpecSharpGenericMethodParameterDeclaration; //follows from precondition
applicableParameter = (SpecSharpGenericMethodParameterDeclaration)genericMethodParameter;
break;
}
if (applicableParameter == null) {
this.HandleError(name.SourceLocation, Error.TyVarNotFoundInConstraint);
applicableParameter = new SpecSharpGenericMethodParameterDeclaration(null, name, (ushort)genericMethodParameters.Count);
}
this.Skip(Token.Colon);
this.ParseGenericMethodParameterConstraints(applicableParameter, followers|Token.Where);
}
this.SkipTo(followers);
}