On Tue, 3 Nov 2015 19:37:04 +0100 Ondrej Pokorny <laza...@kluug.net> wrote:
> On 03.11.2015 17:34, Mattias Gaertner wrote: > > codetools use only a simple heuristic to calculate the type of a > > binary operator. > > The function TFindDeclarationTool.CalculateBinaryOperator needs to be > > extended for Alias types (e.g. 'integer' instead of longint) and for > > ranges (e.g. if the operands do not fit into an integer). > > Maybe you are talking about the same, but just to be sure: IMO using > hard-coded alias types is not a good idea (theoretically the user can > redefine them). No, I meant that 'integer' is defined as type integer = longint; For the compiler 'integer' is just an alias for longint. But codetools should use the alias as much as possible instead of the underlying base type. Maybe I should have used 'SizeInt' as an example. SizeInt can be longint or int64. When a function returns SizeInt codetools should declare the variable as SizeInt instead of the current base in order to help creating cross platform code. > Instead the type evaluation should go to the end type > (e.g. from Integer to *longint*) and then the end types should be > compared. The comparison can then be done with a hard-coded table (you > need it only for the basic types, so it is OK and safe) and the type > that wins, will be used as the result type (obviously the originally > used alias). > > E.g.: > > procedure Test; > var > I: Integer; > S: SmallInt; > begin > Res := I + S; > end; > > Something like: > 1.) > I = (Integer -> longint) > S = SmallInt > 2.) > ResultBasicType = Compare(longint, SmallInt) -> longint -> I > 3.) > ResultType = ResultBasicType -> I -> *Integer* That would fail with the following example: var i: SizeInt; j: SmallInt; begin k:=i+j; end; The result should be SizeInt, not Integer. Of course there are some hard coded defaults in codetools. For example "i:=3" can be any integer type. In TP/Delphi/LCL applications "integer" is used so often it is a good default. Same for "String". But what type should "i:=3.0" create? Single, Double, Extended, glFloat? It would be nice if codetools could guess the "usual" type from the surrounding code or if it can be set via an IDE/project/package option. Mattias -- _______________________________________________ Lazarus mailing list Lazarus@lists.lazarus.freepascal.org http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
