Re: [PATCH, Fortran] Internal documentation for gfc_expr

[Tobias Burnus <burnus at net-b dot de>]

Daniel Kraft wrote:
> attached is a patch and changelog that creates a new section 
> "gfc_expr" in the "Front-end data structures" chapter of 
> gfc-internals.texi describing how expressions are structured.
+@c XXX: Other index keys?

I think that is currently not needed.

+Expressions and ``values'', including constants, variable-, array- and
+component-references as well as complex expressions built of operators and
+function calls [...]

Instead of "built of" I would use "consisting of" or something similar.

+the type, rank and eventually shape of the whole expression or expression tree


"eventually" sounds strange (Oxford Dict. of Engl.: "occurring or 
existing at the end of or as a result of a process or period of time"). 
How about ", if applicable, "?

+@c XXX: Make subsections nodes of their own and create a menu?

One could do so, however, the subsections are currently quite short and 
thus I think it is currently not needed.

+@code{expr_type} set to @code{EXPR_CONSTANT}.  The constant's value should
s/should/shall/

+some operator on one or two operands.  These have an @code{expr_type} of
s/These/The expressions/  ("These" can otherwise be confused with "operands".)


+should be evaluated on these operands, where @code{uop} describes a user-defined
+overloaded operator.

I would remove "overloaded".  For operator(+) one overloads it, but for operator(.myop.) not.


+function symbol if the call is to an intrinsic or user-defined function,
I wonder whether "external" is better than "user-defined" or not.


+@c XXX
+@c What good is EXPR_SUBSTRING?  When is it used?

Well, as the name already tells: When matching a substring, e.g.  "abcde"(1:2) the expressions is a EXPR_SUBSTRING. The expression contains then a gfc_ref of the type REF_SUBSTRING. [Cf. primary.c (match_varspec and match_string_constant).]


Except for the minor nits, the patch looks OK.

By the way, thanks for your fantastic coding and documenting work! Too bad that we currently have a reviewing deficit. I will try to have another look at your huge patch, though I still hope that Paul has soon time to review it. He knows that part of gfortran best.

Tobias