4 ms·

F’23 doesn’t have much in it that’s new over F’18, which itself was also a pretty minor update to F’08. One thing to watch out for: in a departure from former

F’23 doesn’t have much in it that’s new over F’18, which itself was also a pretty minor update to F’08. One thing to watch out for: in a departure from former commitments to compatibility, F’23 changes some semantics of working conforming code, specifically allocatable characters being used for internal writes, iomsg=, &c.

imachine1980_ 3y ago
> allocatable characters being used for internal writes can you explain this ?
- pklausler 3y ago
  If you allocate a character object, then write to it with an internal write statement, F’23 now requires that the variable be reallocated to the actual length of the formatted record, instead of retaining its former length and being padded out with blanks (or truncated). The LLVM Fortran compiler (Flang) has warnings for various usages whose semantics would change if F'23 semantics were adopted by default, which I'm not sure I want to do.
  - EE84M3i 3y ago
    I've never used fortran so I'm not sure what a character object or an internal write is, but in C would this be something like allocating a character array and sprintf-ing to it?
    - pklausler 3y ago
      That's a good analogy, with the change being that sprintf is now somehow required to reallocate your buffer on every call if the length ever changes.
bee_rider 3y ago
It must be hard to update a language that was already perfect in 1990.
- nolist_policy 3y ago
  Fortran first appeared in 1957... It's probably older than most people here on HN.
  - fuzztester 3y ago
    "The first significantly widespread high-level language was Fortran." https://en.m.wikipedia.org/wiki/High-level_programming_language https://en.m.wikipedia.org/wiki/High-level_programming_langu...
  - bee_rider 3y ago
    As the other comment pointed out, F90 is surprisingly good considering it is also probably older than most people on this site, haha.
  - EVa5I7bHFq9mnYK 3y ago
    It's just 34 more yeats until F'57 becomes ambigous ..
    - bee_rider 3y ago
      I think you’ve made a typo, > yeats It is yeets, two e’s no a.
  - pmcjones 3y ago
    Lots of information here: https://www.softwarepreservation.org/projects/FORTRAN/ https://www.softwarepreservation.org/projects/FORTRAN/
- pklausler 3y ago
  F'90 lacked allocatable derived type components, but was otherwise very well thought out, and its major contributions (modules, free form, internal procedures, generic interfaces, ELEMENTAL, array syntax, POINTER/TARGET...) have held up well. Kind of a mixed bag since then, frankly (FORALL, LEN type parameters, FINAL, ENUM, DO CONCURRENT...)
- 3y ago

imachine1980_ 3y ago

> allocatable characters being used for internal writes can you explain this ?

pklausler 3y ago
If you allocate a character object, then write to it with an internal write statement, F’23 now requires that the variable be reallocated to the actual length of the formatted record, instead of retaining its former length and being padded out with blanks (or truncated). The LLVM Fortran compiler (Flang) has warnings for various usages whose semantics would change if F'23 semantics were adopted by default, which I'm not sure I want to do.
- EE84M3i 3y ago
  I've never used fortran so I'm not sure what a character object or an internal write is, but in C would this be something like allocating a character array and sprintf-ing to it?
  - pklausler 3y ago
    That's a good analogy, with the change being that sprintf is now somehow required to reallocate your buffer on every call if the length ever changes.

bee_rider 3y ago

It must be hard to update a language that was already perfect in 1990.

nolist_policy 3y ago
Fortran first appeared in 1957... It's probably older than most people here on HN.
- fuzztester 3y ago
  "The first significantly widespread high-level language was Fortran." https://en.m.wikipedia.org/wiki/High-level_programming_language https://en.m.wikipedia.org/wiki/High-level_programming_langu...
- bee_rider 3y ago
  As the other comment pointed out, F90 is surprisingly good considering it is also probably older than most people on this site, haha.
- EVa5I7bHFq9mnYK 3y ago
  It's just 34 more yeats until F'57 becomes ambigous ..
  - bee_rider 3y ago
    I think you’ve made a typo, > yeats It is yeets, two e’s no a.
- pmcjones 3y ago
  Lots of information here: https://www.softwarepreservation.org/projects/FORTRAN/ https://www.softwarepreservation.org/projects/FORTRAN/
pklausler 3y ago
F'90 lacked allocatable derived type components, but was otherwise very well thought out, and its major contributions (modules, free form, internal procedures, generic interfaces, ELEMENTAL, array syntax, POINTER/TARGET...) have held up well. Kind of a mixed bag since then, frankly (FORALL, LEN type parameters, FINAL, ENUM, DO CONCURRENT...)
3y ago